History Recap / TeenageMutantNinjaTurtlesMutantMayhem

Splinter unlocks the boys' restraints and the mutant family happily reunite. When Leo questions how he found out about their peril, April enters the lab from a side-vent, sheepishly saying that she couldn't not ''try'' to help her friends out of their jam after she partly got them into it. Whilst the Turtles are overjoyed by April's loyalty, Splinter confronts them over the entire mess, demanding to know what the Turtles have been up to on the surface. Whilst the teens try to down play the severity of their predicament, Splinter recognises what the milking machine is (helped by the massive plaque on the side denoting it as the "Mega Milker 2000"). Upset over his sons' lies, and how their recklessness has both resulted in the ''exact'' outcome he repeatedly warned them about and endangered "[[YouAreACreditToYourRace The only good human]], April" through helping Superfly build his machine, Splinter lays down his ultimatum: he and the Turtles will stop Superfly, destroy the machine, and then return to the sewers. Permanently. Ordering April back to the safety of her own home as well, Splinter reprimands his sons once more, stating that they can only be safe and happy by listening to him and following his orders.

Reeling from the realization of how low he's falling by [[JerkassRealization allowing his fear and hatred of humanity to dictate how he treats his own family]], Splinter is shocked out of his funk when Superfly calls out to him for aid with his predicament. The gang leader points out to the elderly rat that their shared hatred of humans is exactly the same; the only difference being, he's not a passive "punk" about dealing with the threat they bring, unlike Splinter. Upset by realizing how correct Superfly is, that insult is the last straw for the rat-man, who charges in and puts his own weight behind the combined mutant press against Superfly. The combined effort is enough to tip the balance against Superfly, the mutants pushing him through the control panel and forcing him backwards into the Ooze-filled generator below the machine, badly electrocuting him. The damage done to the supports is too much to allow them to lift the machine anymore, and the whole thing collapses down atop Superfly, the weight tearing a hole through the bottom of the tanker and taking the ooze-filled generator down along with the fly mutant to the bottom of the ocean.

Donnie points out to Leo that despite their best efforts, they couldn't stop Superfly ''before'' he turned into a massive {{Kaiju}} super-mutant, and their odds have dwindled into practically non-existence now. Mickey points out that it'd make more sense to let the human army show up and stop the beast instead, with Donnie concurring that they do eventually show up in every {{Franchise/Godzilla}} movie he's watched, only for Splinter to [[BigNo cut their defeatist talk off]]. Splinter admits he's let his fear and hatred of humanity get the better of him, and that he'd become too similar to Superfly for it liking because of it. But he loves his sons, and wants the best for them and if they want humanity to like them, they the united mutants will support them in that endeavour. So they'll be the ones to take down [=SuperDuperFly=], film it to show the world that they're heroes underneath their freakish appearance, and earn the acceptance of humanity that way. Inspired by his Speech, Bebop and Rocksteady say they're 100% behind them on that endeavour, but point out the logical issue: how ''exactly'' are they gonna stop a 100-foot tall mutant that can squash ''them'' like flies?

As Raph despairs over their dreams of being "normal" coming to naught, Leo instead refuses to be cowed by their failure. Admitting that April had a point; that their attempts to be heroes as a selfish means of being accepted was wrong, he still thinks there's worth in them saving the day and being heroes, accepted or not. When Mikey points out how all their plans failed, Leo just retorts that his brother knows how to [[IndyPloy improvise on his feet]] better than any of them, even Mark Ruffalo. When Donnie cites how impossible it would be to fight a giant monster like [=SuperDuperFly=], Leo reminds him Anime-obsessed brother that he's read more comic books and consumed more media about people fighting giant monsters than anybody, so he'll ''absolutely'' be able to think of an impossible plan for them to follow. After a moment's consideration, Donnie has EurekaMoment: recalling the ''Attack on Titan'' scribble, he remembers how the titular monsters' AchillesHeel was located on the backs of their necks, and as Mikey points to a news camera footage of [=SuperDuperFly=] on the billboards, they see that his whale body's blowhole is located exactly there, pulsing with exposed green mutagen. Ejecting the remaining anti-mutagen canister from the gun, Donnie theorises that if they insert it into the blowhole, it'll spread the formula throughout the entire amalgamated monster's bloodstream, de-mutating all the assimilated animals at once. Turning to Raph, Leo commends his brother's anger-fulled strength, asking him to use it to help them by going "as loud as you can". Amped up by his brother's speech, Raph races over to an crashed Pizza van and single-handedly lifts it back onto its wheels. Their sprits rejuvenated, the quartet pile into the van as Raph commends Leo for his superb leadership moment.

'''leo:''' I do? Oh, ''I do!!'' Oh, I sound like ''such'' a leader, holy crap, that's so dope!\\

Confused, Splinter looks around as more humans crowd around him offering aid, before his gaze falls on April's live broadcast on the billboards, the news changed to now support the Turtles and the mutants as heroes fighting against [=SuperDuperFly=]. Realizing he doesn't need to fear their actions anymore, Splinter begs the citizens to get the anti-mutagen canister to his sons, with one of them dropping it in a plastic carrier bag for easy carrying before running down the street towards [=SuperDuperFly=]'s attempted execution. Seeing the humans trying to aid the Turtles makes the Super-Mutant pause before trying to thwart the nameless helper, tossing more cars his way. Before he can be crushed, Genghis Frog hops in to give him a piggy-back ride through the projectiles, dodging several of them before [=SuperDuperFly=] blocks their way with a thrown bus. At that moment, a New York cab driver speeds by, yelling to the civilian to pass him the canister instead, as he takes up the charge instead. [=SuperDuperFly=] again collapses the street in front of the cab with a thrown projectile, only for Wingnut and Scumbug to lift the whole vehicle over the blockade. When another projectile knocks the cab from their grip, Bebop and Rocksteady safely catch it, passing the canister onto Mondo Gecko who, with the aid of some scarer hoodlums, is able to weave his way past [=SuperDuperFly=]'s barrage, underneath his legs before accidentally falling into a broken storm drain that's flooded the streets behind him... allowing Ray Fillet to swim in and pass the canister from Mondo onto a tower crane operator riding the hook towards the Turtles.

As [=SuperDuperFly=] is stumped by the seamless cooperation between mutant and human against him, he's unexpectedly hurt by a bulldozer ramming into his leg, followed swiftly by multiple other vehicles driven by new Yorkers united against him slamming into his reachable limbs. The pain makes him release his death grip on the Turtles, making them desperately scramble to keep ahold of his massive body as the {{Kaiju}} Mutant is further distracted by more civilians opening the apartment windows around him to throw whatever they can lay their hands on onto his head. No freed, the Turtles use their acrobatic skills and teamwork to Parkour around the nearby buildings and the Super-Mutant's body, passing the canister from one to the other until Leo is finally able to slice the bag open and drop the canister into [=SuperDuperFly=]'s blowhole, the teenagers triumphantly posing around the Ooze-spewing orifice at their success.

-->'''[=SuperDuperFly=]:''' Damm! You think this the end of me? man, you know what-

Soon after, the Mutants move into the sewers with the Turtles and Splinter, settling in to life in the lair. Ray Fillet enjoying the tunnels' acoustics, Mondo performing pipe tricks on his skateboard as recorded by Genghis, Wingnut enjoying reading through Donnie's manga collection, Bebop and Rocksteady arguing over where the couch should go and Leatherhead cooking dinner for them. Splinter and Scumbag make packed lunches for the Teenagers, now wearing their human clothes in preparation for their first day in the human world above ground. Reassuring his sons that they can come to him for aid if they run into trouble (and the rest of their extended family will join in) the teenagers reassure him that Splinter's prepared them for this moment their whole lives. After reaffirming their family love for each other, the turtles venture up top, leaving their father with their trademark face-obscuring headgear as they head out to Eastman high, just as normal teenagers. Despite initial trepidation, the student body warmly welcomes the heroic teens, and the Quartet catch up with April as she shows them around, walking past her locker as they do so, the graffiti on it now re-named to "April O'hero"...

In a mid-credit scene, the Turtles are shown enjoying high school life: Michelangelo is participating in the school's comedy improv team just like he wanted, Raphael has joined the wrestling team to focus his aggression into healthier interests, Donatello has found the computer club ("My people!"), and Leonardo helping April out with her journalistic interests as her cameraman. April's next focus is TCRI, whose offices were mysteriously cleaned out following the aftermath of [=SuperDuperFly=]'s rampage, all personnel vanished without a trace. However, April (and Leo) vows to track them down wherever they've gone to ground. Once the recording's done, Leo bashfully and awkwardly asks April that, prom being back on and all, if she'd be willing to go to the dance with him. April accepts (though under the opinion that it's just as friends). Later on at the dance, as the four turtles mess around and socialise with their fellow teenagers, they are unknowingly watched by a secret spy camera, monitored by Cynthia Utrom, nearby a sealed contianement jar containing a buzzing fly -- all that remains of Superfly after the anti-mutagen affected him. Cynthia comments that finding the Turtles will be much easier than expected; ''capturing'' them, with the approval of the public behind them however, will be much less so. The Squad Leader speaks up, noting that they do have ''one'' option...

A trio of thugs coordinate an heist on a van containing a radioactive storage unit under orders from Superfly, faking a traffic diversion to lure it into a side-street so they can blow the tires out with spikes and switch the Storage Unit unto their getaway vehicle of an ice-cream truck. Whilst successful, the increased police presence on the streets as a result of the crime wave has them swiftly noticed and pursued by the cops, getting cut off with a police blockade ahead of them. Seeing no way out, the thugs prepare of their imminent capture...before a giant winged shadowy ''thing'' grabs onto the top of the ice cream truck and bodily lifts the whole thing up over the blockade, flying through the city skyline to the panic of its unwitting passengers. The truck continues flying past the city limits, eventually approaching an abandoned and derelict tanker ship washed up in an old ship graveyard, and gets dropped within by their flying "rescuer". Disorientated from the fall, the thugs look around their surroundings to see more shadowy, inhuman forms moving in the shadows of the tanker, surrounding them. The truck's doors get ripped open and a menacing inhuman shadow approaches them through the smoke, to the mounting horror of the thugs as they [[MassOhCrap realize]] what this thing is.

-->'''Thug:''' You--you really are...\\

With his earliest memories being of how his father Stockman yearned for acceptance and wanted to achieve that with his mutant family, after losing him to TCRI's attack, the baby Superfly wandered through the city with the vials of his siblings in his arms before coming across the abandoned tanker, seeking shelter within. As the oldest of the mutants, Superfly took it upon himself to raise them, scavenging food and supplies to feed them as they all steadily grew up. Watching TV commercials of human life in their home, the Mutant crew, despite acknowledging that they lost their father to humans, still believed that maybe not ''every'' humans was as bad as his attackers. Like the Turtles, they too tried to integrate into Human civilisation, heading out into a street side cafe to greet the humans... and like the Turtles, they too were met with fear and rejections, ultimately fleeing for their lives from an angry mob. Whilst the turtles admit they too had a similar experience, Superfly recounts that in their case, there was one particularly determined aggressor, a human who chased after his family with a baseball bat, either not realizing or not caring that the mob hadn't followed after them. In contrast to Splinter's decision to remain in hiding (which Superfly derides as a "punk" choice) the bug mutant instead turned on his aggressor, [[BullyingADragon violently beating him down to within an inch of his life]]. The experience taught Superfly two things: that Human-Mutant integration was impossible, and how ''good'' it felt to hurt humans instead of taking their abuse. To that end, he came up with a Plan to achieve his acceptance: [[KillAllHumans killing all the humans]] and letting mutant kind rule the earth instead.

Reeling from the realisation of how low he's falling by [[JerkassRealisation allowing his fear and hatred of humanity to dictate how he treats his own family]], Splinter is shocked out of his funk when Superfly calls out to him for aid with his predicament. The gang leader points out to the elderly rat that their shared hatred of humans is exactly the same; the only difference being, he's not a passive "punk" about dealing with the threat they bring, unlike Splinter. Upset by realizing how correct Superfly is, that insult is the last straw for the rat-man, who charges in and puts his own weight behind the combined mutant press against Superfly. The combined effort is enough to tip the balance against Superfly, the mutants pushing him through the control panel and forcing him backwards into the Ooze-filled generator below the machine, badly electrocuting him. The damage done to the supports is too much to allow them to lift the machine anymore, and the whole thing collapses down atop Superfly, the weight tearing a hole through the bottom of the tanker and taking the ooze-filled generator down along with the fly mutant to the bottom of the ocean.

The massive groaning sounds again as ''something'' gigantic shakes the entire tanker moving underneath it, the green glow of the Ooze fading as something swims away through the bay waters. The mutant rush topside to see the glowing mass breaching the surface, revealing it to be Superfly, now fused with a bunch of Aquatic marine life into a gigantic mutant abomination, particularly a whale as the main body with his compound fly eyes, crawling on the beach surface as it steadily makes its way into the city streets, ooze dribbling from its polluted insides like saliva. Thanks to lacking legs though, the super-mutant is limited to squirming on its belly and making slow progress with the aid of Superfly's remaining pincer arm, prompting Leo to voice that at least its impaired mobility means things aren't ''that'' bad for them...only for the Super-mutant to reach the nearby Rosebank Zoo and hurl itself into it, the Ooze fusing and combining it with the animal inhabitants into a bipedal form, a left arm formed of marine life like Narwals, animals like giraffes fusing into its face, and legs formed from mammals like horses.

In the present, in the underground sewers of New York City, four shadowy reptilian figures don face masks and test out their ninja weaponry, a staff, Nunchaku, Sai and Swords. Bursting from a sewer grate, the four acrobatically parkour across the rooftops before the clouds pass and illuminate them in the moonlight, revealing them to be humanoid mutant turtles, clad in Ninja outfits. Their blue-clad leader, Leonardo, reiterates the importance of the mission their master, Splinter, has provided them tonight, that it will take all of their stealth, skill and cunning to infiltrate the human world and retrieve the important items from their list....starting with Gogurt. The other three turtles (Michelangelo, Raphael, and Donatello) start mocking Leo for his "Batman voice" in trying to hype up their mission, deflating the tension and revealing that the quartet are teenagers out on a shopping trip for supplies for their home, such as ice cream and Doritos. After dividing up the tasks they need to achieve for the night, Leo reminds his brothers that they cannot be seen by any humans whilst out getting supplies, as per their master's reminder...

Despite that, all the brothers agree that they actually think humans and their culture is pretty cool, speaking admirably of several stars like Beyonce and Guy Fieri, before Leo reluctantly reminds them that they've got a job to do regardless. Using their ninja skills to remain out of sight, the brothers successfully steal supplies from corner shops, shipping containers at the docks and cargo trucks mid-transport. After successfully fulfilling all the items on their list, the brothers reconvene on a rooftop, passing by a billboard announcement noting the rising crime wave in the city....committed instead by a criminal mastermind known only by his street nickname of "Superfly", with his latest successful theft of an Industrial-Grade power converter raising concerns amongst New Yorkers enough that parents have started calling for a curfew after dark until the crime lord is caught. Noting that they've succeeded in fulfilling Splinter's tasks, Leo is ready to head home, only for his brothers to object, pointing out that they've only been out for an hour, and they can afford to spend a little more time out exploring the wonders of the human world. Despite Leo's objections that they'd agreed to stop spending so much time out enjoying human activities like watching baseball games or concerts, Donny notes that their Shut-In of a father won't know how long it takes them to gather their supplies, and the trio happily head off to catch a late-night movie viewing in Madison Square gardens, followed reluctantly by leo.

As the Turtles grew older and became more curious about the surface, he decided to take them on a trip outside to see if their altered state would allow them to interact with humans better. Emerging into the streets above, the family's amazement with the bright lights and sounds of the city swiftly turned to fear when the civilians (particularly ones adjacent to a silver-painted statue guy and a mascot in a homemade-looking SpongeBob costume) noticed their inhuman appearances, an angry mob swiftly forming intending to attack them, After nearly losing Mikey to a traffic accident, Splinter swiftly fled with his sons back into the sewers. Convinced from the experience that humans would never accept his family and would attack them on sight, Splinter realized there was only one logical way to protect themselves...turning their bodies into weapons of destructions through Japanese ninjutsu. Using old video tapes and kung-fu movies, scavenging the Turtles' weapons and gear from around the city, Splinter spent the next 15 years training his family into the stealthy ninjas they've become by the present day, even if his own advanced age means he is not able to accompany them on their surface shopping trips anymore.

Catching up to the present, Splinter sadly notes that he's so strict with their topside activates because their small mutant family is all he'll ever have, them being the only mutants in the world, and he's terrified of losing his sons from them interacting with a world that hates and fears them on sight. Though reluctant, Splinter grounds the Turtles for one month, forbidding them from leaving the sewers, with Raph, Donny and Mikey making their displeasure towards Leo for this punishment he brought on them clear. Afterwards, the four brothers sadly discuss what they'd do if they could actually interact normally with the human world without fears of being rejected, talking about their dreams of going to high school, making friends their own age and even getting a girlfriend in Leo's case. Moping over the impossibility of their dreams, the Quartet eventually go to sleep.

One month later, after their punishment has ended, the Turtles goof off with their ninja weaponry on a rooftop during one of their supply runs, recording themselves using Leo's katana to slice watermelons in mid-air, to his disgruntlement. Deciding to one-up their performance, Raph gets the idea to use a ninja star on the target next, having Mikey [[WilliamTelling hold a melon aloft (that happens to be shaped exactly like his head)]] whilst he aims and Donny records. Despite Mikey's trepidation, Raph hits the target, only for the star to burst through the melon and fly out onto the street below, causing a collision. Worried by the sounds, Leo rushes over to the lip of the roof to see their ninja star hit a passing scooterist in her biker helmet and caused her to crash. [[LoveAtFirstSight Instantly smitten by the sight of her]], Leo is knocked out of his revere by the girl's angry tirade at them for their irresponsible actions and the danger of chucking weaponry into a busy street, unable to see the Quartet clearly from street level.

Confused by their strange appearance, the thugs discuss amongst themselves if their intruders are preforming mascots or something else whilst the panicking brothers try to think of some way to resolve the mess they're in, Donny pointing out that they've never been in a fight ''period'' until right now. Raph, [[BloodKnight eager for a fight]], overides their objections to try and charge into their opposition, only to mess up, accidentally stab Donny in the leg and blow up the rest of his brothers with an air canister. Despite the poor first start, the turtles' muscle memories of their training as well as their natural agility and adaptability enables them to hold their own in a fight, even as the situation spirals further out of control and a fire starts inside the shop. After thwarting the leader's last-ditch attempt to use a car as a ramming tool against them, the brother exult in their victory, only for the girl to suddenly enter the shop, having successfully followed them, forcing them to quickly hide as best they can whilst setting her scooter upright.

Getting texts from their respective parents to return home, April and the turtles part ways after exchanging contact info. On their way back through the sewer tunnels, the teens exult again over the night's events, wanting to experience most positive contact with the human world and the adrenaline rush of their fight. When Leo brings up April's point about only feeling goodwill towards the turtles because their actions proved they weren't;t dangerous, Donny get the idea to do the same thing on a larger scale. Pointing to an announcement of the latest theft of Superfly's, he points out that if the brothers were to track the dangerous criminal down, use their ninja skills to capture him and turn him into the police, it'd get them seen as heroes citywide. Once the adulations had died down, they could use that to enrol in normal high school and be accepted by the populace at large. Excited for the chance to live their dreams (and Leo wanting to see more of April) the Quartet agree to proceed with the plan, getting April's cooperation to meet at her high school of Eastman high to outline their plan of attack, whilst Spliter grows suspicious of his sons' enthusiasm on leaving...

Parkouring through the City, the brothers meet up with April outside the high school, becoming awestruck at the mundane interior of the building as she walks them through it, with Donnie geeking out over an ''Manga/AttackOnTitan'' scrawl on one of the lockers, finding camaraderie in his nerdy interests with the owner. Mikey likewise is enthused by a sign-up sheet for a comedy improv club, desiring to get his name added ahead of schedule in preparation for them eventually joining the school, believing their plan to capture Superfly will be complete in a few weeks. Briefly stymied by the sheet needing a last name (and the Quartet realising they don't actually ''[[NoFullNameGiven have]]'' those, Mikey decides to just cleave up his name to make "Michael Angelo" instead. When Raph and Donny tease Leo by realising the same logic would make his name "Leo [[InherentlyFunnyWords Nardo]]", he attempts to deflect by pointing out a nearby locker with "Puke Girl" scrubbed across it, claiming Nardo's still better than that. When noticing April's flustered reaction to that and seeing a further scribble of "April O'Puke", Raph realizes that it's ''her'' locker, forcing a reluctant April to admit the truth to the brothers.

... Cue April ''exploding'' with vomit all over the desk, broadcast throughout the entire school, eventually fainting whilst still spewing her guts out. Humiliated, April admits the incident when utterly viral, resulting in her getting remixed, memed and winding up on Tiktok, ensuring she was widely known as a social pariah amongst her peers. April states that the real reason she was looking for Superfly was so she could have a journalistic success that enabled her to remain off-camera, whilst also hoping that by getting the Prom un-cancelled, she'd be known for something cool that could let her move on from being "Puke Girl", [[NotSoDifferentRemark explicitly comparing]] her motivations with the Turtles' own.

In the school's photography class dark room, April shows the brothers her hidden [[StringTheory assembled board of Superfly's past crimes]], explaining that his heists indicate he's using the stolen technology to build something, "some real ''{{WesternAnimation/Megamind}}''-type stuff", whilst using street thugs as pawns to ensure he stays under the radar, additionally killing anybody who witnesses him in person.

With Donnie driving the van containing the assimilator to the setting point (thanks to his long hours of playing ''Forza Horizon'') the Turtles prepare to ambush Superfly, in radio communication with April hiding nearby and ready to record the entire exchange. Superfly's crew soon arrive, rolling up in a monster truck, a motorcycle and a souped-up muscle car, with Leo estimating they only have to contend with 10 goons, tops. As Raph excitedly grins that he can't wait to see their shock at facing a bunch of mutants instead of their buyers, the monsters truck driver and motorbike user step out in front of their headlights...revealing themselves to be a large, hulking mutant Warthog and Rhinoceros, to the teen's collective shock. Playing a boombox track to accompany his entrance, the criminal mastermind himself steps out of the muscle car, revealing that Superfly is the grownup version of Baxter's fly mutant, multi-armed, muscular and imposing as he struts towards the van. The rest of his crew emerge from their vehicles, revealing that all of them are the mutated animals Baxter intended to be his children.

With his earliest memories being of how his father Stockman yearned for acceptance and wanted to achieve that with his mutant family, after losing him to TCRI's attack, the baby Superfly wandered through the city with the vials of his siblings in his arms before coming across the abandoned tanker, seeking shelter within. As the oldest of the mutants, Superfly took it upon himself to raise them, scavenging food and supplies to feed them as they all steadily grew up. Watching TV commercials of human life in their home, the Mutant crew, despite acknowledging that they lost their father to humans, still believed that maybe not ''every'' humans was as bad as his attackers. Like the Turtles, they too tried to integrate into Human civilisation, heading out into a street side cafe to greet the humans... and like the Turtles, they too were met with fear and rejections, ultimately fleeing for their lives from an angry mob. Whilst the turtles admit they too had a similar experience, Superfly recounts that in their case, there was one particularly determined aggressor, a human who chased after his family with a baseball bat, either not realising or not caring that the mob hadn't followed after them. In contrast to Splinter's decision to remain in hiding (which Superfly derides as a "punk" choice) the bug mutant instead turned on his aggressor, [[BullyingADragon violently beating him down to within an inch of his life]]. The experience taught Superfly two things: that Human-Mutant integration was impossible, and how ''good'' it felt to hurt humans instead of taking their abuse. To that end, he came up with a Plan to achieve his acceptance: [[KillAllHumans killing all the humans]] and letting mutant kind rule the earth instead.

Leo awakens to find himself and his brothers [[StrappedToAnOperatingTable restrained in a strange machine]] and surrounded by TRCI goons. Cynthia Utrom enters the room, greeting her captives and saying that she's been looking for them for a long time, pleased to have finally captured some of Baxter's mutant creations. When Donny tries to protest against their captivity and warn Utrom about the danger that Superfly's plan brings to them all, she shuts him up with [[ElectricTorture an electric shock]], making it clear that she's not interested in hearing anything they have to say, or what motivations that brought them into her clutches. Cynthia curtly tells the Turtles that they are ''her'' "property", repeatedly shocking the brothers when they try to speak up, and explains to them that she intends to use them to reverse-engineer Baxter's mutagen, planning on using the stabilised formula to create an army of mutant super-soldiers: Dolphin mutants to plant submersible bombs, Eagle mutants for Ariel combat and Snake-men mutants for stealthy infiltrations. When the confused brothers query how they can possibly be expected to aid with all that, Cynthia reveals there's only one way to drain the mutagen out of them -- through their blood. As she excitedly orders them to get hooked up to the machine, the teenagers realize to their horror that their father was right: the humans intend to milk them to death.

The door opens to reveal an empty hallway...before Splinter falls down from the vents above, his advanced age preventing him being as stealthy as his sons. Splinter tries to bargain with the TCRI goons menacing him, telling them he doesn't want a fight, just to take his sons back home (whilst also making it very clear to the captured Turtles that they are in a ''lot'' of trouble for their deception). When the goons refuse to release them and make it clear they plan to suck Spinter's mutagen out as well, the elderly rat gets serious, using his greater martial arts mastery to utterly wipe the floor in seconds with his aggressors, turning their own stun batons back on them despite [[CrackOwMyBack throwing out his back doing so]]. Realising that Splinter won't go down easily, a chaotic fight erupts as the entire building's security forces descend on the lab, openly firing on Splinter with their anti-mutagen weapons and pursuing him around the lad as he creatively uses his environment to stay one step ahead of them. Eventually however, their sheer numbers seem to overwhelm Splinter, shocking him and knocking him backwards into a storage cabinet that falls atop him and crushes him...only for Splinter to cut his way out of the cabinet, brandishing all of his son's weapons at once, the ninjutsu weaponry having been kept within. Armed with the weapons he's been training his sons with for years, Splinter [[CurbstompBattle single-handedly beats every last one]] of his armed and armoured foes, even smacking the squad leader down with a GroinAttack from Mikey's nunchuck...and a [[OffhandBackhand followup strike to the jaw]] when he still tries to rise back up.

At Superfly's hideout, The mutant family infiltrate the tanker ship, lit from within by the green glow of Superfly's machine hooked up to his mutagen supplies. Finding the place seemingly abandoned, Mikey queries if they gave up and left the machine behind, only for Superfly to turn the lights on, revealing it was a trap they laid for the turtles' eventual interference with their plan. Surrounded by his crew (with Mondo being pleased to see their cousins again) the Turtles are prepared to fight through their mutant brethren if necessary to stop the machine being used, even if they're reluctant to fight their kin. Irritated and confused by their persistent objections to his goal despite their mutant nature, Superfly demands to know what the Turtles find so amazing about humanity that they're turn on their own kind for it. Donny admits that humans have bad people amongst them like Cynthia Utrom, but says they also have good people like April too, being complicated creatures. Splinter joins in on the argument, admitting that, despite his immense dislike of the human world (and he's still adamant about how much he dislikes them) he cannot stand back and let the mutants wipe out humanity, pointing out to them that doing so makes them just as bad as their oppressors.

Reeling from the realisation of how low he's falling by [[JerkassRealisation allowing his fear and hatred of humanity to dictate how he treats his own family]], Splinter is shocked out of his funk when Superfly calls out to him for aid with his predicament. The gang leader points out to the elderly rat that their shared hatred of humans is exactly the same; the only difference being, he's not a passive "punk" about dealing with the threat they bring, unlike Splinter. Upset by realising how correct Superfly is, that insult is the last straw for the rat-man, who charges in and puts his own weight behind the combined mutant press against Superfly. The combined effort is enough to tip the balance against Superfly, the mutants pushing him through the control panel and forcing him backwards into the Ooze-filled generator below the machine, badly electrocuting him. The damage done to the supports is too much to allow them to lift the machine anymore, and the whole thing collapses down atop Superfly, the weight tearing a hole through the bottom of the tanker and taking the ooze-filled generator down along with the fly mutant to the bottom of the ocean.

Donny points out to Leo that despite their best efforts, they couldn't stop Superfly ''before'' he turned into a massive {{Kaiju}} super-mutant, and their odds have dwindled into practically non-existence now. Mickey points out that it'd make more sense to let the human army show up and stop the beast instead, with Donny concurring that they do eventually show up in every Godzilla movie he's watched, only for Splinter to [[BigNo cut their defeatist talk off]]. Splinter admits he's let his fear and hatred of humanity get the better of him, and that he'd become too similar to Superfly for it liking because of it. But he loves his sons, and wants the best for them and if they want humanity to like them, they the united mutants will support them in that endeavour. So they'll be the ones to take down [=SuperDuperFly=], film it to show the world that they're heroes underneath their freakish appearance, and earn the acceptance of humanity that way. Inspired by his Speech, Bebop and Rocksteady say they're 100% behind them on that endeavour, but point out the logical issue: how ''exactly'' are they gonna stop a 100-foot tall mutant that can squash ''them'' like flies?

At that moment, April phones the Turtles, witnessing [=SuperDuperFly=]'s rampage from her bedroom window, asking her friends how the heck their attempt to stop the mutant criminal turned into this chaotic mayhem!? Donny sheepishly admits that a '''lot''' happened since they split up, and leo desperately question April if she's got any ideas as to how they could stop the Super-Mutant. Though incredulous that they're counting on her to think of a solution, April's gaze falls on the stolen TCRI bike parked outside her apartment....with one of the Anti-Mutagen guns strapped to it. Seeing a possible hope to save the day, April says she'll meet the mutants at the base of [=SuperDuperFly=]'s leg, tearing off through the streets towards the chaos as panicking citizens flee around her. Re-invigorated, the mutants head off as one across the bay, Mondo surfing atop Ray Fillet, Ghengis Frog and Leatherhead naturally swimming through the waters, Wingnut carrying Bebop and Rocksteady, and Scumbug carrying the Turtle family a cargo net, whilst accidentally dribbling goop all over them, to their disgust.

[=SuperDuperFly=] kicks an abandoned gas tanker like a football towards them, the massive explosion blowing the heroes away. [[ShellShockSilence Dazed from the blast]], a groggy Mikey witnesses [=SuperDuperFly=] swat Wingnut from the sky, whilst Bebp tries to lift a crashed truck off of Rocksteady. Seeing what happens to be part of mondo's tail crushed underneath rubble, Mikey tries to pull him loose, only to have the tail come off in his hands to his horror...before Mondo runs past him for cover, assuring Mikey his mutation let him grow limbs like that easily. Mikey turns around to see a stunner Donny making his way to him, unaware of [=SuperDuperFly=] throwing abandoned vehicles towards him from behind, until Raph tackles him out the way. Taking cover from the Super-mutant's vehicular assault, the brothers try to figure out where everybody is, as Leo shows up, acrobatically dodging [=SuperDuperFly=]'s projectiles. With a nearby parking garage offering him plenty of ammunition, the Quartet have no choice but to flee, grabbing the mutagen gun as they do. Their attempt to hide inside an abandoned bus fails to escape [=SuperDuperFly=]'s notice, and he punts the vehicle with it passengers through the air, having it land several blocks away as he exults in how unstoppable he is.

As Raph despairs over their dreams of being "normal" coming to naught, Leo instead refuses to be cowed by their failure. Admitting that April had a point; that their attempts to be heroes as a selfish means of being accepted was wrong, he still thinks there's worth in them saving the day and being heroes, accepted or not. When Mikey points out how all their plans failed, Leo just retorts that his brother knows how to [[IndyPloy improvise on his feet]] better than any of them, even Mark Ruffalo. When Donny cites how impossible it would be to fight a giant monster like [=SuperDuperFly=], Leo reminds him Anime-obsessed brother that he's read more comic books and consumed more media about people fighting giant monsters than anybody, so he'll ''absolutely'' be able to think of an impossible plan for them to follow. After a moment's consideration, Donny has EurekaMoment: recalling the ''Attack on Titan'' scribble, he remembers how the titular monsters' AchillesHeel was located on the backs of their necks, and as Mikey points to a news camera footage of [=SuperDuperFly=] on the billboards, they see that his whale body's blowhole is located exactly there, pulsing with exposed green mutagen. Ejecting the remaining anti-mutagen canister from the gun, Donny theorises that if they insert it into the blowhole, it'll spread the formula throughout the entire amalgamated monster's bloodstream, de-mutating all the assimilated animals at once. Turning to Raph, Leo commends his brother's anger-fulled strength, asking him to use it to help them by going "as loud as you can". Amped up by his brother's speech, Raph races over to an crashed Pizza van and single-handedly lifts it back onto its wheels. Their sprits rejuvenated, the quartet pile into the van as Raph commends Leo for his superb leadership moment.

As the Turtles' van zooms through the wreaked streets, Scumbug swoops down, carrying Splinter in her arms to deliver to rodent atop the moving van. Explaining that he can converse with the cockroach mutant quite well due to them both speaking "vermin" (and casually admitting he's very attracted to her), Splinter directs Donny to drive to the top of a nearby parking garage, putting them at optimal height to jump the van straight over the passing [=SuperDuperFly=]'s head and letting Mikey drop the canister into his blowhole. Before he can release the missile however, [=SuperDuperFly=] notices the mid-air van above his head from the reflection in a nearby glass skyscraper, swiftly turning around and catching it. Ripping the top off the van, he seizes the Turtles in his claw arm, causing Micky to drop the canister. Though Splinter manages to jump from the falling van to catch the anti-mutagen, he's left wide open to [=SuperDuperFly=] backhanding him several blocks away, landing painfully and left lying prone on the ground. Angered by their repeated interference with his anti-human campaign, [=SuperDuperFly=] declares that he's ''done'' with the Turtles, mocking them that they'll never be capable of stopping him, ''or'' getting accepted by humans, before using his claw arm as a lever to start crushing the teenagers, wanting to crack their shells "like pistachios". As the pressure mounts and their demise seems imminent, Raph takes back his earlier statement, admitting that [[ItHasbeenAnHonor he's happy his last sight will be his brother's faces]].

Soon after, the Mutants move into the sewers with the Turtles and Splinter, settling in to life in the lair. Ray Fillet enjoying the tunnels' acoustics, Mondo performing pipe tricks on his skateboard as recorded by Genghis, Wingnut enjoying reading through Donny's manga collection, Bebop and Rocksteady arguing over where the couch should go and Leatherhead cooking dinner for them. Splinter and Scumbag make packed lunches for the Teenagers, now wearing their human clothes in preparation for their first day in the human world above ground. Reassuring his sons that they can come to him for aid if they run into trouble (and the rest of their extended family will join in) the teenagers reassure him that Splinter's prepared them for this moment their whole lives. After reaffirming their family love for each other, the turtles venture up top, leaving their father with their trademark face-obscuring headgear as they head out to Eastman high, just as normal teenagers. Despite initial trepidation, the student body warmly welcomes the heroic teens, and the Quartet catch up with April as she shows them around, walking past her locker as they do so, the graffiti on it now re-named to "April O'hero"...

In a mid-credit scene, the Turtles are shown enjoying high school life: Michaelangelo is participating in the school's comedy improv team just like he wanted, Raphael has joined the wrestling team to focus his aggression into healthier interests, Donatello has found the computer club ("My people!"), and Leonardo helping April out with her journalistic interests as her cameraman. April's next focus is TCRI, whose offices were mysteriously cleaned out following the aftermath of [=SuperDuperFly=]'s rampage, all personnel vanished without a trace. However, April (and Leo) vows to track them down wherever they've gone to ground. Once the recording's done, Leo bashfully and awkwardly asks April that, prom being back on and all, if she'd be willing to go to the dance with him. April accepts (though under the opinion that it's just as friends). Later on at the dance, as the four turtles mess around and socialise with their fellow teenagers, they are unknowingly watched by a secret spy camera, monitored by Cynthia Utrom, nearby a sealed contianement jar containing a buzzing fly -- all that remains of Superfly after the anti-mutagen affected him. Cynthia comments that finding the Turtles will be much easier than expected; ''capturing'' them, with the approval of the public behind them however, will be much less so. The Squad Leader speaks up, noting that they do have ''one'' option...

On a dark night, a van races through the streets of New York City. Inside, a Techno Cosmic Research Institute strike force is ordered by executive Cynthia Utrom to capture rogue scientist Baxter Stockman, who stole billions of dollars' worth of company secrets and technology, and used it to create a biological weapon -- a living mutant. To counteract the danger of his creation, the strike force with armed with guns containing high-powered, anti-mutant neutralizer solutions, which will theoretically de-mutate the monster. Inside his makeshift lab in an abandoned building, Stockman refines several chemicals throughout the scientific apparatus, watched over by his puppy-sized mutant creation from a nearby crib, a housefly maggot. The process finally finishes, resulting in a vial of glowing green Ooze, to Stockman's delight, as he exults to his "little one" that he finally managed to perfect the Ooze. Contrary to expectations, Stockman tells the mutant that he has no desire for it to be used as a weapon, or any others like it. Feeling ostracised from other humans for all of his life and feeling more of a connection to the animals he's experimented on, the lonely MadScientist instead created his mutant child solely to start a family together, having likewise created mutagen formulas that support embryonic creatures that he intends to be the housefly's siblings. Before he can create more mutagen, the strike force arrives, breaking into the lab and subduing Stockman, failing to notice the vial of perfected Ooze he has clutched within his sleeve.

However, when the strike force tries to seize the mutant fly, its crib is empty. Scurrying around the darkness of the lab, the flight-capable and surprisingly strong fly mutant strikes and subdues the strike force members one by one, finally leaving only their leader as the last one standing. Latching onto his unprotected face, the fly mutant scratches out his left eye, and in pain he starts wildly firing the anti-mutagen gun around the lab trying to hit his attacker. The fly mutant lands on some unstable chemical canisters, and Baxter's pleas not to shoot go unheeded by the enraged leader, forcing him to seize his "child' and protect him from the resulting explosion with his body. When the smoke clears, all that is left is Baxter's prone body on the lab floor, his research papers burned and damaged, and the mutant nowhere to be found, along with the vials containing the embryonic family members, with only an open widow showing what became of them. Though upset by their failure, Cynthia orders the strike team to recover Baxter's body and any surviving scraps of research they can get, stating that Baxter's creation ''must'' live on, so that a new world will write itself. Unnoticed by the TCRI goons, the vial of perfected Ooze that was within Stockman's sleeve falls free as they are moving his corpse, rolling into a nearby drain grating and falling into the sewers below...

In the present, in the underground sewers of New York City, four shadowy reptilian figures don face masks and test out their ninja weaponry, a staff, Nunchaku, Sai and Swords. Bursting from a sewer grate, the four acrobatically parkour across the rooftops before the clouds pass and illuminate them in the moonlight, revealing them to be humanoid mutant turtles, clad in Ninja outfits. Their blue-clad leader, Leonardo, reiterates the importance of the mission their master, Splinter, has provided them tonight, that it will take all of their stealth, skill and cunning to infiltrate the human world and retrieve the important items from their list....starting with Gogurt. The other three turtles (Michaelangelo, Raphael, and Donatello) start mocking Leo for his "Batman voice" in trying to hype up their mission, deflating the tension and revealing that the quartet are teenagers out on a shopping trip for supplies for their home, such as ice cream and Doritos. After dividing up the tasks they need to achieve for the night, Leo reminds his brothers that they cannot be seen by any humans whilst out getting supplies, as per their master's reminder...

On reaching their sewer home and trying to sneak in under the cover of darkness, the quartet are surprised by their father figure, Master Splinter, waiting for them in his armchair, surprising them by turning the lights on and revealing that he's an elderly mutated rat. Suspicious about the length of time the boys have taken whilst "shopping", he pressures them about their whereabouts until Leo eventually cracks and admits the truth. Disgusted at the idea of the teenagers staying out to watch a human movie, and upset that they don't see it as a big deal, Splinter decides to remind the teenagers of the reason why they cannot interact with humans, on top of them being "disgusting monsters who'll milk [them] for their blood". When the Turtles protest over hearing the tale ''again'', Splitner decides [[AsYouKnow he'll regale them with the extra-long version]] just for that. 15 years ago, Splinter was once an ordinary rat in his mid-twenties and was at the bottom of the pecking order, [[HatedByAll hated by fellow rats, racoons and dogs]], with humans being the ones who most attacked him whilst he was out scavenging for food. He only possessed one friend in the world -- Kevin, a cockroach...who was stepped on by a passing human. And then [[BlackComedyCannibalism had his corpse eaten]] by a hungry Splinter.

As the Turtles grew older and became more curious about the surface, he decided to take them on a trip outside to see if their altered state would allow them to interact with humans better. Emerging into the streets above, the family's amazement with the bright lights and sounds of the city swiftly turned to fear when the civilians noticed their inhuman appearances, an angry mob swiftly forming intending to attack them, After nearly losing Mikey to a traffic accident, Splinter swiftly fled with his sons back into the sewers. Convinced from the experience that humans would never accept his family and would attack them on sight, Splinter realised there was only one logical way to protect themselves...turning their bodies into weapons of destructions through Japanese ninjutsu. Using old video tapes and kung-fu movies, scavenging the Turtles' weapons and gear from around the city, Splinter spent the next 15 years training his family into the stealthy ninjas they've become by the present day, even if his own advanced age means he is not able to accompany them on their surface shopping trips anymore.

A trio of thugs coordinate an heist on a van containing a radioactive storage unit under orders from Superfly, faking a traffic diversion to lure it into a side-street so they can blow the tires out with spikes and switch the Storage Unit unto their getaway vehicle of an ice-cream truck. Whilst successful, the increased police presence on the streets as a result of the crime wave has them swiftly noticed and pursued by the cops, getting cut off with a police blockade ahead of them. Seeing no way out, the thugs prepare of their imminent capture...before a giant winged shadowy ''thing'' grabs onto the top of the ice cream truck and bodily lifts the whole thing up over the blockade, flying through the city skyline to the panic of its unwitting passengers. The truck continues flying past the city limits, eventually approaching an abandoned and derelict tanker ship washed up in an old ship graveyard, and gets dropped within by their flying "rescuer". Disorientated from the fall, the thugs look around their surroundings to see more shadowy, inhuman forms moving in the shadows of the tanker, surrounding them. The truck's doors get ripped open and a menacing inhuman shadow approaches them through the smoke, to the mounting horror of the thugs as they realise what this thing is.

-->'''Thug:''' You...you really are...\\

The terrified thugs' [[GoryDiscretionShot final screams]] ring out throughout the ship, revealed to be the abandoned property of TCRI...

At the headquarters of TCRI, Cynthia Utrom is brooding over the numbers failed specimens stacked in jars around her office; all failures at attempting to replicate Stockman's mutagen formula. The squad leader (now sporting a metallic eyepatch over his damaged eye) enters to inform her of the Stogage unit's theft, the latest of several brazen attacks targeting TCRI machinery. Seeing the news report of the flying ice cream truck, Cyntia's attention turns back to the framed remnants of Stockman's research notes in her office, her eyes drawn to the barely-legible burned scrap of paper demoting the "housefly" experiment. Putting the pieces together, Cynthia orders the squad leader to put tracking devices on all their machine shipments going forward, planning to meet the mysterious criminal targeting her company and finish what they started long ago...

Surprised by the utterly thrashed state of the thugs and her scooter being laid out in pristine condition for her, the girl soon spots the brothers' flimsy attempts to hide in the shadows of the shop, asking them to come out so she can properly thank them for saving her scooter, deciding their good deed makes them square for the ninja star incident. With no way to hide, the brothers eventually emerge from the shadows, leaving the girl surprised by the "realistic costumes" on these crime-fighters until she tries to get them off and realises that they're real. On the verge of a FreakOut, Mikey manages to diffuse the tension by asking if the girl is cool with some Pizza whilst they explain everything about themselves.

Parkouring through the City, the brothers meet up with April outside the high school, becoming awestruck at the mundane interior of the building as she walks them through it, with Donnie geeking out over an ''Manga/AttackOnTitan'' scrawl on one of the lockers, finding camaraderie in his nerdy interests with the owner. Mikey likewise is enthused by a sign-up sheet for a comedy improv club, desiring to get his name added ahead of schedule in preparation for them eventually joining the school, believing their plan to capture Superfly will be complete in a few weeks. Briefly stymied by the sheet needing a last name (and the Quartet realising they don't actually ''[[NoFullNameGiven have]]'' those, Mikey decides to just cleave up his name to make "Michael Angelo" instead. When Raph and Donny tease Leo by realising the same logic would make his name "Leo [[InherentlyFunnyWords Nardo]]", he attempts to deflect by pointing out a nearby locker with "Puke Girl" scrubbed across it, claiming Nardo's still better than that. When noticing April's flustered reaction to that and seeing a further scribble of "April O'Puke", Raph realises that it's ''her'' locker, forcing a reluctant April to admit the truth to the brothers.

Following her journalistic desires, April thought she could get a start in that by reading the school's morning announcements, only for her first time in front of the cameras to be more overwhelming that she'd realised. Hit by a massive anxiety attack, April felt like she was going to explode from the stress...

As the small Mutant convoy peels out, followed by April on her scooter, The brothers furiously argue amongst themselves as to what to fro next, Leo passing the buck to Donnie to come up with a plan of attack. To buy time, Donnie questions Mondo about their destination, with the friendly lizard revealing Superfly's base of operations is the abandoned tanker in a shipping graveyard on Staten Island. Following behind, April says that the Turtles better make their move now, only for Raph to veto the possibility of them being able to win a close-range with a bulky Juggernaut like Rocksteady. Leo realises that if the turtles can hit the van's breaks, all three mutants, sitting in the front seats, would be ejected whilst the Brothers could hold on in the back of the van, thanks to Superfly tearing away the windshield earlier. Using Donnie's staff to reach the pedal underneath the seats and under the cover of the mutant crew singing along to the radio, Mikey eventually pushes the brakes and causes the van to crash to a halt, flinging the trio out and letting the Turtles hijack it and the cargo, fleeing away pursed by the angry crew, April following closely behind. Unnoticed by the Turtles, the assimilator has a beeping tracker on it, operating in the back of the van as the chase continues through the streets...

Leo awakens to find himself and his brothers [[StrappedToAnOperatingTable restrained in a strange machine]] and surrounded by TRCI goons. Cynthia Utrom enters the room, greeting her captives and saying that she's been looking for them for a long time, pleased to have finally captured some of Baxter's mutant creations. When Donny tries to protest against their captivity and warn Utrom about the danger that Superfly's plan brings to them all, she shuts him up with [[ElectricTorture an electric shock]], making it clear that she's not interested in hearing anything they have to say, or what motivations that brought them into her clutches. Cynthia curtly tells the Turtles that they are ''her'' "property", repeatedly shocking the brothers when they try to speak up, and explains to them that she intends to use them to reverse-engineer Baxter's mutagen, planning on using the stabilised formula to create an army of mutant super-soldiers: Dolphin mutants to plant submersible bombs, Eagle mutants for Ariel combat and Snake-men mutants for stealthy infiltrations. When the confused brothers query how they can possibly be expected to aid with all that, Cynthia reveals there's only one way to drain the mutagen out of them -- through their blood. As she excitedly orders them to get hooked up to the machine, the teenagers realise to their horror that their father was right: the humans intend to milk them to death.

Outside, April and the Turtles' path diverge on the steps of the TCRI building, Leo taking a moment to apologise to her for their failure to uncancel the prom. April brushes it off, admitting to Leo that seeing the brothers' screw-ups in their quest to gain popularity with the public made her realise she also wasn't following the Superfly story for the right reasons, turning away from her friends as they walk away into the night, Leo taking one last look at her before following. April's return home is thwarted however, by her scooter having burst its tire from the intense chase, leaving her with no easy way back. As she curses her luck, more TCRI goons zip past April on hi-tech motorbikes, parking outside the building as the goons rush inside to provide backup for their colleagues within, as April's gaze shifts to the still-idling motorbike...

Staring down at Superfly's watery grave, alit with the glow of the submerged mutagen, Mikey hesitantly asks if they managed to stop the threat of Superfly's mutagen plan, to which Splinter uncertainly says that it seems to have worked, only to be cut off by an inhuman groaning from the depths. Mondo quickly realises that in their haste to stop Superfly's machine, they might not have considered the fallout of breaking the ooze-filled weapon.

One month later, after their curfew has ended, the Turtles goof off with their ninja weaponry on a rooftop during one of their supply runs, recording themselves using Leo's katana to slice watermelons in mid-air, to his disgruntlement. Deciding to one-up their performance, Raph gets the idea to use a ninja star on the target next, having Mikey [[WilliamTelling hold a melon aloft (that happens to be shaped exactly like his head)]] whilst he aims and Donny records. Despite Mikey's trepidation, Raph hits the target, only for the star to burst through the melon and fly out onto the street below, causing a collision. Worried by the sounds, Leo rushes over to the lip of the roof to see their ninja star hit a passing scooterist in her biker helmet and caused her to crash. [[LoveAtFirstSight Instantly smitten by the sight of her]], Leo is knocked out of his revere by the girl's angry tirade at them for their irresponsible actions and the danger of chucking weaponry into a busy street, unable to see the Quartet clearly from street level.

Splinter unlocks the boys' restraints and the mutant family happily reunite. When Leo questions how he found out about their peril, April enters the lab from a side-vent, sheepishly saying that she couldn't not ''try'' to help her friends out of their jam after she partly got them into it. Whilst the Turtles are overjoyed by April's loyalty, Splinter confronts them over the entire mess, demanding to know what the Turtles have been up to on the surface. Whilst the teens try to down play the severity of their predicament, Splinter recognises what the milking machine is (helped by the massive plaque on the side denoting it as the "Mega Milker 2000"). Upset over his sons' lies, and how their recklessness has both resulted in the ''exact'' outcome he repeatedly warned them about and endangered "[[YouAreACreditToYourRace The only good human]], April" through helping Superfly build his machine, Splinter lays down his ultimatum: he and the Turtles will stop Superfly, dismantle the machine, and then return to the sewers. Permanently. Ordering April back to the safety of her own home as well, Splinter reprimands his sons once more, stating that they can only be safe and happy by listening to him and following his orders.

Donny points out to Leo that despite their best efforts, they couldn't stop Superfly ''before'' he turned into a massive {{Kaiju}} super-mutant, and their odds have dwindled into practically non-existence now. Mickey points out that it'd make more sense to let the human army show up and stop the beast instead, with Donny concurring that they do eventually show up in every Godzilla movie he's watched, only for Splinter to [[BigNo cut their defeatist talk off]]. Splinter admits he's let his fear of humanity get the better of him, and that he'd become too similar to Superfly for it liking because of it. But he loves his sons, and wants the best for them and if they want humanity to like them, they the united mutants will support them in that endeavour. So they'll be the ones to take down [=SuperDuperFly=], film it to show the world that they're heroes underneath their freakish appearance, and earn the acceptance of humanity that way. Inspired by his Speech, Bebop and Rocksteady say they're 100% behind them on that endeavour, but point out the logical issue: how ''exactly'' are they gonna stop a 100-foot tall mutant that can squash ''them'' like flies?

As she makes her way into the studio, pushing past all the fleeing reporters and news crew from [=SuperDuperFly=] rampaging just outside the building, April bursts into the studio just as the newscaster flees the broadcast as the building partially collapses. Despite her anxiety and old trauma returning once more when she realises she's back in front of a live camera crew again, April manages to control herself to deliver the correct series of events to New York (minus a little vomiting), outlining that the only mutant they need to fear is [=SuperDuperFly=], and the others are risking their lives to stop him.

As the Turtles' van zooms through the wreaked streets, Scumbug swoops down, carrying Splinter in her arms to deliver to rodent atop the moving van. Explaining that he can converse with the cockroach mutant quite well due to them both speaking "vermin" (and casually admitting he's very attracted to her), Splinter directs Donny to drive to the top of a nearby parking garage, putting them at optimal hight to jump the van straight over the passing [=SuperDuperFly=]'s head and letting Mikey drop the canister into his blowhole. Before he can release the missile however, [=SuperDuperFly=] notices the mid-air van above his head from the reflection in a nearby glass skyscraper, swiftly turning around and catching it. Ripping the top off the van, he seizes the Turtles in his claw arm, causing Micky to drop the canister. Though Splinter manages to jump from the falling van to catch the anti-mutagen, he's left wide open to [=SuperDuperFly=] backhanding him several blocks away, landing painfully and left lying prone on the ground. Angered by their repeated interference with his anti-human campaign, [=SuperDuperFly=] declares that he's ''done'' with the Turtles, mocking them that they'll never be capable of stopping him, ''or'' getting accepted by humans, before using his claw arm as a lever to start crushing the teenagers, wanting to crack their shells "like pistachios". As the pressure mounts and their demise seems imminent, Raph takes back his earlier statement, admitting that [[ItHasbeenAnHonor he's happy his last sight will be his brother's faces]].

Confused, Splinter looks around as more humans crowd around him offering aid, before his gaze falls on April's live broadcast on the billboards, the news changed to now support the Turtles and the mutants as heroes fighting against
[=SuperDuperFly=]. Realising he doesn't need to fear their actions anymore, Splinter begs the citizens to get the anti-mutagen canister to his sons, with one of them dropping it in a plastic carrier bag for easy carrying before running down the street towards [=SuperDuperFly=]'s attempted execution. Seeing the humans trying to aid the Turtles makes the Super-Mutant pause before trying to thwart the nameless helper, tossing more cars his way. Before he can be crushed, Genghis Frog hops in to give him a piggy-back ride through the projectiles, dodging several of them before [=SuperDuperFly=] blocks their way with a thrown bus. At that moment, a New York cab driver speeds by, yelling to the civilian to pass him the canister instead, as he takes up the charge instead. [=SuperDuperFly=] again collapses the street in front of the cab with a thrown projectile, only for Wingnut and Scumbug to lift the whole vehicle over the blockade. When another projectile knocks the cab from their grip, Bebop and Rocksteady safely catch it, passing the canister onto Mondo Gecko who, with the aid of some scarer hoodlums, is able to weave his way past [=SuperDuperFly=]'s barrage, underneath his legs before accidentally falling into a broken storm drain that's flooded the streets behind him... allowing Ray Fillet to swim in and pass the canister from Mondo onto a tower crane operator riding the hook towards the Turtles.

On a rainy night, a thunderstorm illuminates a figure watching the city of new York, his visage obscured with a very familiar looking spiked helm...

At Suerfly's hideout, The mutant family infiltrate the tanker ship, lit from within by the green glow of Superfly's machine hooked up to his mutagen supplies. Finding the place seemingly abandoned, Mikey queries if they gave up and left the machine behind, only for Superfly to turn the lights on, revealing it was a trap they laid for the turtles' eventual interference with their plan. Surrounded by his crew (with Mondo being pleased to see their cousins again) the Turtles are prepared to fight through their mutant brethren if necessary to stop the machine being used, even if they're reluctant to fight their kin. Irritated and confused by their persistent objections to his goal despite their mutant nature, Superfly demands to know what the Turtles find so amazing about humanity that they're turn on their own kind for it. Donny admits that humans have bad people amongst them like Cynthia Utrom, but says they also have good people like April too, being complicated creatures. Splinter joins in on the argument, admitting that, despite his immense dislike of the human world (and he's still adamant about how much he dislikes them) he cannot stand back and let the mutants wipe out humanity, pointing out to them that doing so makes them just as bad as their oppressors.

In a mid-credit scene, the Turtles are shown enjoying high school life: Michaelangelo is participating in the school's comedy improv team just like he wanted, Raphael has joined the wrestling team to focus his aggression into healthier interests, Donatello has found the computer club ("My people!"), and Leonardo helping April out with her journalistic interests as her cameraman.

now focused on TCRI who have mysteriously disappeared since the events of the film. While the five are later enjoying themselves at the school prom, Cynthia, who is spying on them (and with the now unmutated Superfly by her side) decides that the focus is to capture the Turtles by bringing in a mysterious asset called "The Shredder".

Soon after, the Mutants move into the sewers with the Turtles and Splinter, and the Turtles enroll at April's high school, where they are all embraced as heroes.

In a mid-credit scene, the Turtles are shown enjoying high school life: Michaelangelo is participating in the school's comedy improv team, Raphael has joined the wrestling team, Donatello has found the computer club, and Leonardo (who, throughout the film, has developed a crush on April) has decided to help her with her journalistic interests, now focused on TCRI who have mysteriously disappeared since the events of the film. While the five are later enjoying themselves at the school prom, Cynthia, who is spying on them (and with the now unmutated Superfly by her side) decides that the focus is to capture the Turtles by bringing in a mysterious asset called "The Shredder".

The Turtles, Splinter, April, and the Mutants are recognized as heroes by the city, and the boys reconcile with their father, who apologizes for his xenophobic behavior. Soon after, the Mutants move into the sewers with the Turtles and Splinter, and the Turtles enroll at April's high school, where they are all embraced as heroes.

As the Turtles' van zooms through the wreaked streets, Scumbug swoops down, carrying Splinter in her arms to deliver to rodent atop the moving van. Explaining that he can converse with the cockroach mutant quite well due to them both speaking "vermin" (and casually admitting he's very attracted to her), Splinter directs Donny to drive to the top of a nearby parking garage, putting them at optimal hight to jump the van straight over the passing [=SuperDuperFly=]'s head and letting Mikey drop the canister into his blowhole. Before he can release the missile however, [=SuperDuperFly=] notices the mid-air van above his head from the reflection in a nearby glass skyscraper, swiftly turning around and catching it. Ripping the top off the van, he seizes the Turtles in his claw arm, causing Micky to drop the canister. Though Splinter manages to jump from the falling van to catch the anti-mutagen, he's left wide open to [=SuperDuperFly=] backhanding him several blocks away, landing painfully and left lying prone on the ground. Angered by their repeated interference with his anti-human campaign, [=SuperDuperFly=] declares that he's ''done'' with the Turtles, mocking them that they'll never be capable of stopping him, ''or'' getting accepted by humans, before using his claw arm as a lever to start crushing the teenagers, wanting to crack their shells "like pistachios". As the pressure mounts and their demise seems imminent, Raph takes back his earlier statement, admitting that [[FaceingTheBulletsOneLiner he's happy his last sight will be his brother's faces]].

While the Turtles, Splinter, and the Mutants fight, April is able to overcome her anxiety and explain on live air to the public what is going on, leading the citizens of New York to help stop him [=SuperDuperFly=]. Donatello discovers that the blowhole on the back of his neck carries a massive amount of mutagen, and the Turtles are able to drop a canister of anti-ooze into [=SuperDuperFly=]'s blowhole, returning him to being a regular fly.

[=SuperDuperFly=] kicks an abandoned gas tanker like a football towards them, the massive explosion blowing the heroes away. [[ShellShockedSilence Dazed from the blast]], a groggy Mikey witnesses [=SuperDuperFly=] swat Wingnut from the sky, whilst Bebp tries to lift a crashed truck off of Rocksteady. Seeing what happens to be part of mondo's tail crushed underneath rubble, Mikey tries to pull him loose, only to have the tail come off in his hands to his horror...before Mondo runs past him for cover, assuring Mikey his mutation let him grow limbs like that easily. Mikey turns around to see a stunner Donny making his way to him, unaware of [=SuperDuperFly=] throwing abandoned vehicles towards him from behind, until Raph tackles him out the way. Taking cover from the Super-mutant's vehicular assault, the brothers try to figure out where everybody is, as Leo shows up, acrobatically dodging [=SuperDuperFly=]'s projectiles. With a nearby parking garage offering him plenty of ammunition, the Quartet have no choice but to flee, grabbing the mutagen gun as they do. Their attempt to hide inside an abandoned bus fails to escape [=SuperDuperFly=]'s notice, and he punts the vehicle with it passengers through the air, having it land several blocks away as he exults in how unstoppable he is.

The Turtles, Splinter, the Mutants, and April head to mainland New York City to stop him once and for all. While the Turtles, Splinter, and the Mutants fight, April is able to overcome her anxiety and explain on live air to the public what is going on, leading the citizens of New York to help stop him [=SuperDuperFly=]. Donatello discovers that the blowhole on the back of his neck carries a massive amount of mutagen, and the Turtles are able to drop a canister of anti-ooze into [=SuperDuperFly=]'s blowhole, returning him to being a regular fly.

With his earliest memories being of how his father Stockman yearned for acceptance and wanted to achieve that with his mutant family, after losing him to TCRI's attack, the baby Superfly wandered through the city with the vials of his siblings in his arms before coming across the abandoned tanker, seeking shelter within. As the oldest of the mutants, Superfly took it upon himself to raise them, scavenging food and supplies to feed them as they all steadily grew up. Watching TV commercials of human life in their home, the Mutant crew, despite acknowledging that they lost their father to humans, still believed that maybe not ''every'' humans was as bad as his attackers. Like the Turtles, they too tried to integrate into Human civilisation, heading out into a street side cafe to greet the humans... and like the Turtles, they too were met with fear and rejections, ultimately fleeing for their lives from an angry mob. Whilst the turtles admit they too had a similar experience, Superfly recounts that in their case, there was one particularly determined aggressor, a human who chased after his family with a baseball bat, either not realising or not caring that the mob hadn't followed after them. In contrast to Splinter's decision to remain in hiding (which Superfly derides as a "punk" choice) the bug mutant instead turned on his aggressor, [[BullyingADragon violently beating him down to within an inch of his life]]. The experience taught Superfly two things: that Human-Mutant integration was impossible, and how ''good'' it felt to hurt humans instead of taking their abuse. To that end, he came up with a Plan to achieve his acceptance: [[KillEmAll killing all the humans]] and letting mutant kind rule the earth instead.

Staring down at Superfly's watery grave, alit with the glow of the submerged mutagen, Mikey hesitantly asks if they managed to stop the threat of Superfly's mutagen plan, to which Splinter uncertainly says that it seems to have worked, only to be cut off by an inhuman groaning from the depths.

Unfortunately, the ooze enlarges and combines Superfly with other local wildlife into a bipedal whale-like creature who dubs himself "[=SuperDuperFly=]", deciding to attack New York City. The Turtles, Splinter, the Mutants, and April head to mainland New York City to stop him once and for all. While the Turtles, Splinter, and the Mutants fight, April is able to overcome her anxiety and explain on live air to the public what is going on, leading the citizens of New York to help stop [=SuperDuperFly=]. Donatello discovers that the blowhole on the back of his neck carries a massive amount of mutagen, and the Turtles are able to drop a canister of anti-ooze into [=SuperDuperFly=]'s blowhole, returning him to being a regular fly.

'''The Shadow:''' (''SlasherSmile'') [[NotHyperbole Superfly.]]

The gang agrees and everyone fights Superfly, destroying the machine in the process.

Splinter unlocks the boys' restraints and the mutant family happily reunite. When Leo questions how he found out about their peril, April enters the lab from a side-vent, sheepishly saying that she couldn't not ''try'' to help her friends out of their jam after she partly got them into it. Whilst the Turtles are overjoyed by April's loyalty, Splinter confronts them over the entire mess, demanding to know what the Turtles have been up to on the surface. Whilst the teens try to down play the severity of their predicament, Splinter recognises what the milking machine is (helped by the massive plaque on the side denoting it as the "Mega Milker 4000). Upset over his sons' lies, and how their recklessness has both resulted in the ''exact'' outcome he repeatedly warned them about and endangered "[[YouAreACreditToYourRace The only good human]], April" through helping Superfly build his machine, Splinter lays down his ultimatum: he and the Turtles will stop Superfly, dismantle the machine, and then return to the sewers. Permanently. Ordering April back to the safety of her own home as well, Splinter reprimands his sons once more, stating that they can only be safe and happy by listening to him and following his orders.

When they reach the island, Leonardo and Splinter plead to the conscious of Superfly's gang, stating that if they enslave humanity then they are no better than the humans themselves. The gang agrees and everyone fights Superfly, destroying the machine in the process.