Instances of Small Role, Big Impact in Live-Action Films.
- Vasquez in Aliens. She makes the choice to disregard Gorman's orders not to discharge their weapons while in the Alien hive and conspires with Drake to reactivate their smartguns as soon as Sgt. Apone's back is turned. This leads to the coolant system being ruptured when she and Drake subsequently fire on the aliens. The Marines are later faced with spending 17 days waiting for a rescue, and it's only when Bishop discovers the reactor is going to blow that they come up with the plan to bring the other dropship down from the Sulaco. Given that the aliens later overun their position anyway, had they not brought the second dropship down, they'd have had no means of rescuing Newt, let alone escaping. There's a chance that Ripley, Bishop and a severely wounded Hicks would survive 17 days on LV-426 with no ammunition, but it seems unlikely. That then means no Alien³ or Alien: Resurrection... all because Vasquez brought spare batteries for her smartgun and disobeyed a direct order.
- Babe: Pig in the City has Snoop the airport sniffer dog. He only appears briefly, but in his limited screen time when demonstrating how he does his job at the airport, he unintentionally misinforms the airport security that Esme and Babe are carrying illegal substances and gets them temporarily arrested. This causes them to miss their connecting flight and the whole plot of the movie kicks off from here.
- Back to the Future:
- Back to the Future:
- The "Clock Tower" lady who interrupted Marty and Jennifer's kiss to tell them how lightning struck the Hill Valley clock tower in 1955, giving him a flyer with the exact date and time it happened. If not for her, Marty would have been stuck in 1955, reaching 1985 again only by the natural passage of time.
- The Libyan Terrorists only appear for two scenes (one of these scenes is a repeat of the other) but their attack on Doc and Marty at the beginning of the film is the reason why Marty goes back in time while trying to escape them.
- Back to the Future Part II:
- Griff only appears and is dealt with in the first act, but it's his actions that kick off Marty and Doc's trip to 2015, which in turn kicks off the rest of the film after Marty discovers the almanac.
- The man named Terry in 2015 trying to collect a donation from Marty. The only other thing he does in the movie is commenting on his desire to go back in time to bet the Cubs will win that year's World Series. That comment starts the Almanac plot and is the reason Doc and later Marty go to 1885, resulting in Clara Clayton being saved from falling into a ravine and Jules and Verne Brown existing. If not for this, Doc would have disassembled the Time Machine after he and Marty returned from 2015. His only other appearance in the trilogy is as a car mechanic in 1955 who fixed Biff's car after he wrecked it with the manure truck from the first film.
- Relatedly, the two police officers who find Jennifer and bring her to her future home. In addition to allowing Jennifer to find out about what led Marty to become a Future Loser, their intervention means that instead of heading straight back to 1985, Doc and Marty have to follow them to retrieve Jennifer, which gives Old Biff an opening to steal the DeLorean so he can go back in time and give his younger self the Almanac.
- Back to the Future:
- Ball of Fire has the Garbage Man, who only appears in three scenes, but the slang he uses in his first scene makes Bertram realize he needs to write a whole new chapter on the subject, which kickstarts the entire plot. Also, in his last scene, his question about Damocles gives Bertram and the other professors the idea they need to overpower the gangsters holding them hostage.
- Joe Chill of Batman Begins killed Bruce Wayne's parents, which resulted in a grown up Bruce Wayne becoming Batman.
- The titular Beetlejuice is considered one of Michael Keaton's greatest performances, and the character is still so iconic that he gets referenced often in popular culture nearly 30 years later. Also, he's on-screen less than eighteen minutes, and he doesn't meet the protagonists until the literal halfway point of the movie.
- In Big Daddy, the character of Kevin Gerrity (Jon Stewart) is onscreen for only 20 minutes at the most — less than a quarter of the movie's running time — yet the crux of the film's plot hinges on the protagonist being mistaken for him, a mistake that Gerrity himself can't clear up because he's out of the country for most of the story. He then shows up unexpectedly during the climax and resolves the plot for a happy ending at literally the last possible second.
- In The Big Short, Lewis Ranieri only appears in a flashback scene in the first few minutes of the film. However, because he was the person who first suggested the idea of mortgage-backed securities in 1977, he is responsible for the inflation and eventual bursting of the housing bubble that drives the actions of every major character in the rest of the film. Jared Vennett even observes in his opening narration that most people have never heard of Ranieri, and yet he has had a greater impact on our lives than the social media revolution.
- In The Bourne Identity, Clive Owen has only 3 minutes of screentime as "The Professor", and he never talks until his final scene, almost a half-hour from the end, in which he delivers the series' Arc Words "Look at us. Look at what they make you give."
- Cats & Dogs: After Buddy gets captured by the cats, his role of protecting the Brodys will have to be past down to a replacement puppy.
- John "Dr. Death" Bishop in the first Child's Play movie has only a few minutes of screen time and serves as little more than another person for Chucky to kill. However, John’s role in the series is significant, as Chucky mentions that John was the one who taught him the Dembella chant in the first place, meaning if John hadn’t been around, Chucky would have never been able to transfer his soul into the doll.
- Friday the 13th:
- Friday the 13th Part III: Shelly is little more than The Prankster and one of Jason's many victims, but it's his hockey mask that Jason acquires, netting him his iconic look for the rest of the series.
- Victor from Friday the 13th Part V: A New Beginning. He is only in the film for a few moments, but his murder of Joey results in Roy's rampage. Furthermore, the events of this movie likely played a part in Tommy's continued nightmares and ultimate decision to dig up Jason's grave to try and cremate his body, resulting in his resurrection. In short, the events of the rest of the series can likely be attributed to him.
- In the 1981 film adaptation of Endless Love, Billy appears for barely a minute, but manages to kickstart the second act when he tells David a story about how he, as a kid, set fire to a stack of wet newspapers with the intention of burning his house down, but backed down at the last minute after getting scared, causing him to be hailed as a hero. This inspires David to do the same thing to the Butterfields' house to win their approval back, which goes terribly wrong when he isn't able to extinguish the fire in time.
- The plot of The Gods Must Be Crazy gets underway when an airplane pilot, who never speaks and whose name we never learn, finishes drinking from a Coca-Cola bottle and then throws it out the window, down to the Kalahari Desert below. When the bottle is discovered by a tribe of Bushmen, it triggers a social revolution that results in violence breaking out in Bushman society for the first time, prompting the protagonist to save his village by taking the bottle hundreds of miles across the desert and throwing it into the Atlantic Ocean. Along the way, he encounters white people — and black people too, for that matter, since the Bushmen are technically of a different African racial stock — for the first time, gets his first glimpse of 20th-century Western society, and almost single-handedly captures a band of revolutionary terrorists who had already come close to overthrowing the government of Angola.
- Apollonia in The Godfather Part I was barely seen despite being Michael's wife back in Italy. Her death at the hands of a car bomb drove Michael to become the Corleone's head Don for the entire trilogy.
- Vito's childhood family from Sicily definitely fits this role. His father (who was murdered for standing up to and insulting Don Ciccio) never appears onscreen, His older brother (who was murdered swearing revenge and trying to attack Ciccio and his members) only gets a single scene onscreen... and as a corpse, no less, and finally, his mother insisted that Vito be left alone due to being harmless at the time, and when Ciccio didn't give her mercy, she held him off long enough for Vito to get away at the cost of her own life. None of them last 10 minutes into the film, but they all play a very important role in making Vito the man he is today.
- Moe Greene doesn't have much screentime, but his death provides the motive for the main antagonist of the second movie.
- The Goodbye Girl: Paula's oft-mentioned actor boyfriend Tony DeForest never appears onscreen, but his decision to break up with Paula, leave for Italy, and sublet the apartment to Elliot is what kicks off the entire plot, as well as the eventual romance between Elliot and Paula.
- Greenland: Many characters with important roles in the movie are only onscreen briefly, including another passenger on John's plane who has barely thirty seconds of screen time. He tells John that his nephew got turned away for having a health condition, causing John to realize his family isn't being evacuated and leave the plane to look for them. If not for that other passenger, John would have unknowingly left without them or died during the rioting at the airport.
- Halloween (2018): As the Big Bad Wannabe, Dr. Ranbir Sartain apparently setting Michael Myers free so he can kill again and then Sartain can learn about what he thinks not only has a huge impact in that story, but because Michael is a force of unrelenting evil that cannot be contained once unleashed again—even when he is temporarily recaptured, unwittingly saved from a fire he was trapped in, nearly taken out by a mob and then goes into hiding to recover, Sartain—despite dying at the conclusion of this movie—is ultimately responsible for the inciting incident that makes the events of the whole trilogy happen to begin with.
- Home Alone
- The first film has the McAllister's neighbor, Mitch Murphy, who comes over to watch them leave. While he's curiously checking the transportation shuttle out he gets mistaken for Kevin during a headcount, which is what results in Kevin being left alone.
- Home Alone 2: Lost in New York The man whose coat is identical to Peter's. If not for his presence at the airport, Kevin wouldn't have entered a plane to New York.
- The Hunger Games: Primrose "Prim" Everdeen isn't present for most of the plot, but it's because of her that Katniss ends up in the Games in the first place.
- In The Hunt for Red October, it's one of the low-ranking sub's cooks who singlehandedly prevents Raimey's plan to defect (with the sub) from going smoothly, kicking off the second half of the thriller.
- The salvation of the human race in Independence Day can be traced back to Julius Levinson. While he might appear unassuming as David's sarcastic father, he is able to drive his son all the way to Washington to warn David's ex-wife and the President, which is how they're able to survive. Later, Julius rambles on about Area 51 and its captured spaceship...only to learn that it's totally true. Finally, while David is in a drunken despondent haze, Julius inadvertently gives him the idea to plant a computer virus in the alien mothership in order to allow humanity to fight back. Humorously lampshaded in the sequel Independence Day: Resurgence, which reveals that in in the time gap between the two films he wrote a memoir titled How I Saved the World. (He also gets a dedicated subplot and is one of the few first generation characters to survive to the end.)
- The Uncle in The Innocents, played by Michael Redgrave, appears only for about five minutes at the beginning, but features constantly in Miss Giddens (Deborah Kerr) and the housekeeper's conversations. The fact that Miss Giddens is attracted to him also drives a major plot point, namely Miss Giddens' attraction towards the nephew, Miles, who resembles his uncle very much. Ultimately, the children's tragic fate is as much due to Miss Giddens' warped psychology as the Uncle's constant absence, as he might have dismissed Miss Giddens before the situation went out of control.
- Bruce Lee in Ip Man 4 appears in a handful of scenes but his role impacts a lot of what happens in the film. His teachings inspires his student Hartman Wu to promote Chinese martial arts to the military, resulting in Geddes coming after the Chinese Benevolence Association (CBA). Bruce being Ip's prior student is also what causes tension between Ip and the CBA when Ip tries to apply for an American school for his son.
- James Bond:
- Sylvia Trench has only a couple minutes of screentime during the first two Bond films, Dr. No and From Russia with Love, but she's why Bond introduces himself in his iconic fashion.Bond: I admire your courage, Miss...?
Trench: Trench. Sylvia Trench. I admire your luck, Mister...?
Bond: Bond. [lights cigarette] James Bond. - Even though everyone pictures Donald Pleasence as Ernst Stavro Blofeld, he only plays him in one film, You Only Live Twice, and even then his face is only revealed for less than a half-hour.
- Sylvia Trench has only a couple minutes of screentime during the first two Bond films, Dr. No and From Russia with Love, but she's why Bond introduces himself in his iconic fashion.
- Joker (2019): The three jerks working for Wayne Enterprises only appear for 5 minutes and get killed off by Arthur, but their deaths start the downfall of Arthur and the rise of The Joker. Their deaths also leads to a massive riot against the upper class of Gotham with a clown mask as their symbol, which also leads to the death of their employer Thomas Wayne and his son Bruce Wayne's origin as the vigilante superhero, Batman.
- The Journey of Natty Gann: Connie is directly responsible for the movie's plot and conflict by driving Natty to run away, but her presence in the movie is limited to four minutes of screen-time and two Newhart phone calls.
- The first Lancelot is in Kingsman: The Secret Service for only two scenes at the start, but it's his death what kicks off both storylines given that it opens the position for a new Lancelot and prompts Harry to finish his mission.
- Law Abiding Citizen: Rupert Ames and Clarence Darby have only a few scenes before their deaths, but the Miscarriage of Justice involving these two men is what starts Clyde Shelton on his Roaring Rampage of Revenge.
- Marvel Cinematic Universe:
- Yinsen from Iron Man undeniably fits this trope. He only appeared for a small part of the original Iron Man and made a brief cameo in Iron Man 3. He shares almost as much responsibility for the creation of Iron Man (and by extension the entire MCU) as Tony himself — not only by keeping Tony alive, but by driving him to become a better person, all the way to Tony's heroic sacrifice stopping Thanos and saving the universe.
- Samuel L. Jackson's role as Nick Fury is one of the more famous roles in the Marvel Cinematic Universe as he has appeared in many of the movies and in a few episodes of Agents of S.H.I.E.L.D.. Despite this, he is usually a One-Scene Wonder, appearing in a single scene, some of which, are The Stinger for those films. He likely only has about one hour of screentime spread out throughout the first two phases of the franchise.
- In Captain America: The Winter Soldier, the anonymous SHIELD tech who delayed launching the Insight helicarriers long enough to allow Cap to stop them truly saved the day, considering just how little time Cap had left when he succeeded.
- After having a huge screentime as the Big Bad Villain Protagonist in Avengers: Infinity War, Thanos from Avengers: Endgame has a significantly reduced role in that he only lives as far as the first 15 minutes of the movie before the heroes bring him down for good. However, the fact that he destroys the stones before his death means that the heroes have no way of undoing his fingersnap that turned half the world into dust, leaving them to pick up the rest of the shattered pieces for five years until Ant-Man discovers a way to travel through time to retrieve the stones in order to reverse the effect. This in effect attracts the attention of the Thanos from the past as he learns what his future self did and decides to travel through the present time with the help of Nebula which causes the entire climax of the movie.
- Spider-Man: Homecoming has Jackson Brice. Vulture had a steady criminal operation going on the principles of not getting noticed, but then Brice had to go carelessly firing off the gang's alien weaponry in a residential area, drawing Spider-Man's attention.
- In Spider-Man: Far From Home, J. Jonah Jameson gets approximately 30 seconds of screentime in The Stinger. With those 30 seconds, he manages to out Peter Parker as Spider-Man and implicate him in the attack on London and the "murder" of Quentin Beck.
- In the 1999 movie version of A Midsummer Night's Dream, Hippolyta (the vanquished Amazonian Queen marrying Duke Theseus) is mostly a background figure. However, in the movie when the Duke and his party discover the lovers in the morning, Hippolyta pulls Theseus aside and has some words with him, which go unheard by both the audience and other characters. Afterward Theseus announces that the lovers may marry according to their own wishes, rather than according to the decree of their families.
- Mink in Miller's Crossing only has two short scenes (one of those over the phone), and dies less than halfway in, and yet his "relationship" with both Bernie and Eddie Dane sets off a large part of the plot.
- Trevor Hanaway in Mission: Impossible – Ghost Protocol only shows up in the opening scene and later in a flashback but his failure to obtain the nuclear launch codes is what drives the plot. Also his death at the hands of Sabine is what heavily affects fellow agent (and love interest) Jane's performance in Dubai.
- Dom DeLuise as Bernie the agent in The Muppet Movie gets only a few minutes near the start of the film, but kicks off the plot by convincing Kermit to go to Hollywood and get into showbiz.
- The Blind Seer in O Brother, Where Art Thou? is only in the movie for a couple of minutes or so at the beginning of the film, and for less than a minute at the very end, but his initial scene sets up the adventures of the main characters.
- The Emperor in Onmyōji (2001) is hardly in it bar a couple of scenes in which he does very little that's useful, but it's his rejection of Sukehime that leads to most of the villain's attempts to kill the imperial family via her angry father and her eventual transformation into a demon.
- Pirates of the Caribbean: The Curse of the Black Pearl: As pointed out by the scriptwriters in the DVD Commentary, the entire plot is basically kicked off by Elizabeth Swann's maid pulling her corset too tightly, causing her to fall into the water, causing the cursed coin she's also wearing to summon the undead pirates to Port Royal and capture her, setting off the rescue mission by the other two main characters, Capt. Jack Sparrow and Will Turner, that makes up most of the plot.
- Mayor Beale isn't even in the first Police Academy movie, and only gets a single scene in the first sequel before dropping out of the series entirely, but it's her offscreen decision to change the recruitment standards of the titular academy that sets the entire series in motion.
- Angier's wife Julia in The Prestige. She only has a few scenes but it was her accidental death indirectly at the hands of Borden that started the bitter rivlary between Angier and Borden.
- Red Rock West: When Sheriff Wayne mistakes Michael (a drifter) for the man he hired to kill his wife Suzanne, he gives him a down payment. Michael instead warns Suzanne, mails a letter incriminating Wayne to his deputies, then buys a bunch of food with the down payment and tries to drive out of town. The only problem is that he (literally) runs into Kurt.
- The plot of Saving Private Ryan is kicked off by one woman typing up condolence letters in an office. Through sheer coincidence, she types up the three brothers' letters at once and brings it to the attention of her superior. She has no lines and does not appear past this scene, yet this is what inspires the government to arrange for the fourth brother to be brought home.
- Sarah Paulson's single scene in Serenity sets up the whole third act of the film.
- As an interesting bit of trivia, for this reason Joss Whedon cut down the role of the Operative as Mr Exposition, because he thought it was just far, far scarier for him to be the Implacable Man, and he isn't being implacable when making speeches about Mal as the worthy adversary.
- Jack Palance had a film career of 50 years and over 70 movies, but when he died in 2006, one film role consistently stood out in all the obituaries and tributes dedicated to him: the role of the taunting, smiling hired gun Jack Wilson in Shane. Palance's Wilson is widely regarded as the definitive Western bad guy. Total screen time: eight minutes. Total words spoken by Wilson: less than fifty, but he makes the most out of two of them: "Prove it."
- Shaolin Martial Arts: The entire movie's overall conflict, a fierce duel between the Shaolin and Wing Chun clans, is kicked off when an unnamed Wing Chun student kills a Shaolin student in a supposedly friendly contest, resulting in both sides repeatedly challenging each other, with a dozen deaths before the film ends.
- SHAZAM! (2019): Marilyn Batson, Billy's biological mother, has only made two appearances in the film: First is when she is shown with Billy as a toddler getting separated; second is when Billy finally meets up with her and learns the true background behind the separation. Yet she gives the purpose of showing Billy's personal background of him searching for his mother for past decade, whether it was breaking the law or ditching his foster homes, and his acceptance to embrace his current foster family after realizing that his mother purposely abandoned him at the fair due to a difficult time raising him as a young single mother (she got disowned by her own parents for having Billy at 17-years-old, then her boyfriend got arrested and she was left to raise Billy on her own). Also, without the abandonment, Billy would have never met Freddy Freeman and defended him from bullies which led to him becoming the legendary Shazam.
- The Furies only appear for a few minutes at the climax of Shredder Orpheus, but have a huge impact as they're dispatched to successfully kill Orpheus.
- Anthony Hopkins' first appearance as Hannibal Lecter in Silence of the Lambs last for roughly fifteen minutes. It is an iconic villain role that made him famous and spawned a sequel and a prequel with the actor.
- A very young Rita Moreno appears in Singin' in the Rain as Zelda Zanders exactly four times, the first three with no lines; once as part of the red carpet procession of stars at the premiere of "The Royal Rascal" (accompanied by "J. Cumberland Spendrill III, that well-known eligible bachelor"); once dancing at the after party with some other rich old guy; once watching the "Beautiful Girl" sequence; and once when she sets the climax in motion, leading Lina to the sound studio where Don and Kathy are celebrating the last dub of Lina's lines with a long, passionate kiss.
- Craig and Mary-Ann, the two teens in the opening of Sleepaway Camp who accidentally cause the boating accident that kills most of the Baker family and kicks off the entire franchise. There's also Aunt Martha, who only appears in a handful of scenes, and is the reason why Angela, or rather Peter, kills.
- Sleepers: The boys only wanted a hot dog on a hot summer day and decided to steal some. However, their actions inadvertently led to an elderly man being hospitalized. Shakes narrates and shamefully laments how the boys also caused trouble to the vendor: A Greek immigrant trying to make money to bring his wife and child to the country. Both the old man's family and the vendor, by seeking rightful retribution for the boys' wrongdoings, end up dooming the foursome to juvie.
- Sonic the Hedgehog (2020):
- Longclaw the Owl, Sonic's guardian, only shows up in the first few minutes of the film. But when Sonic was being pursued by the Echidna Tribe, Longclaw decided to give Sonic a bag of rings to send him to Earth while she fends off the Echidna Tribe. Her giving Sonic the bag of rings jumpstarts the plot of the film as Sonic loses his bag of rings and he ends up meeting Tom Wachowski, as well as his nemesis, Dr. Robotnik.
- The Echidna tribe were only in the film for a few minutes like Longclaw. However, it was them chasing after Sonic that caused Longclaw to send Sonic to Earth in the first place.
- Sophie's Choice: The titular character's Sadistic Choice is thrust upon her by an unnamed junior S.S officer. Purely for no reason, other than she happened to be standing there at that point when he walked by.
- Sound of Freedom: Ernst Oshinsky, the pedophile arrested near the beginning of the movie, ultimately and inadvertently sets Ballard off on his mission when he secured Miguel for him. This gives Ballard the opportunity to rescue Miguel and then embark on the more dangerous task of tracking down the boy's sister and rescuing her alongside any other children he can.
- Star Trek II: The Wrath of Khan: Ricardo Montalbán once said that he almost passed on coming back because, as it is written in the script, Khan is actually only onscreen for about fifteen total minutes over the course of the entire movie, and his actual spoken dialogue is pretty minimal as well when compared to the main characters. But then he realized, as he read the story, that Khan's impact on the other characters is present on every single page of the script, and immediately agreed to reprise the role. (It's worth noting that Khan's name hadn't been put in the title yet.)
- Star Wars:
- Darth Vader himself only has a handful of scenes in A New Hope and was originally just The Dragon to Grand Moff Tarkin, but he's the one with a history as Obi-Wan's student and the one who supposedly killed Luke's father, kills Obi-Wan shortly after the halfway point, destroys most of the Rebel Fighters attacking the Death Star and suggests Luke to be a Worthy Opponent. It's no wonder that he graduated to be the primary antagonist in The Empire Strikes Back and revealed to actually BE Luke's father (evidence suggests that Vader and Anakin Skywalker were originally intended to be two different people, but were merged in later drafts of The Empire Strikes Back).
- Darth Maul, for all his popularity, does precisely one thing in The Phantom Menace: kill Qui-Gon Jinn. By doing so, he ensures Anakin is taught by a newly-Knighted Jedi instead of a wise Master with decades of teaching experience, which plays a huge role in his frustration with the Jedi Order and inability to deal with his phenomenal powers, which in turn plays a huge role in his eventual fall and transformation into Darth Vader. Even still, a number of people thought he would be the Darth Vader of the prequels, and were surprised he was killed (presumed at the time) after one film.
- Valorum, the Grand Chancelor before Palpatine, had a rather small role in the entire prequel trilogy, and was replaced by Palpatine halfway through the first movie. However, he was the one who sent Obi-Wan and Qui-Gon to Naboo, which forced Sidious to reveal the existence of the Sith early, and led Obi-Wan to take on Anakin as a padawan.
- Jar Jar Binks got progressively less screentime in the prequels, and only a non-speaking cameo in the last film, but Attack of the Clones had him as a senator propose Chancellor Palpatine get emergency powers in order to militarize the republic and fight the Clone Wars, giving Palpatine's power big legitimacy and the vital step needed to convert the Republic into The Empire in the following film.
- Ensemble Dark Horse status aside, Boba Fett is just one of many bounty hunters sent after Han Solo, only gets marginally more screentime than the rest, and is then anticlimactically killed off by a blinded Han Solo (by accident.) Later materials show him to be alive after killing the Sarlacc. However, he's the one who succeeded in tracking Han, Leia and the gang to Cloud City, meaning everything from Han's capture, to the loss of Luke's hand, the iconic I Am Your Father scene and the entire beginning of Return of the Jedi is all thanks to him.
- In a similar vein, Boba's father Jango only appears for about four scenes in Attack of the Clones, and is killed by Mace Windu on Geonosis, but his death inspires Boba to take up bounty hunting and follow in his footsteps.
- One of the Rebel ships in Rogue One is the Lightmaker. By ramming two Star Destroyers into Scarif's shield gate, it allowed the Rebels to obtain the plans of the Death Star, kickstarting the series of events that would end in the destruction of the Death Star and give the Rebellion a fighting chance.
- Smooth Talk: Arnold Friend’s big scene is under 25 minutes during the last half of the film, but it’s a menacingly memorable one.
- The Joker in Suicide Squad (2016). Firstly, as shown in Flashback, he's responsible for turning Harleen Quinzel into Harley Quinn. His attempted Gunship Rescue of Harley from the Squad is the start of the mission, which had been going (relatively) smoothly until then, going all to hell, and Harley uses his apparent death to trick Enchantress, claiming she will join the mad god in exchange for Joker being brought back to life... so she can get close enough to cut Entrantress' heart out, giving the Squad a chance to save the day.
- Despite not appearing on-screen or mentioned by name, only referenced, Joker is also this in Batman v Superman: Dawn of Justice, his murder of Robin some years before the events of the film being Batman's Cynicism Catalyst.Bruce Wayne: Maybe it's the Gotham City in me. We just have a bad history with freaks dressed like clowns.
- Despite not appearing on-screen or mentioned by name, only referenced, Joker is also this in Batman v Superman: Dawn of Justice, his murder of Robin some years before the events of the film being Batman's Cynicism Catalyst.
- Most of the 1963 Disney film Summer Magic takes place in and around a little country house in Maine sometime before World War I. The house is being leased by the absentee landlord Tom Hamilton, who, despite being at the very least the third-most powerful person in the town, does not appear until less than 30 minutes before the movie ends — and even when he does, it takes a scene or two for him to actually be identified by name.
- Terminator 2: Judgment Day: John's street hooligan friend Tim practically saves the entire human race when he warns John about the "cop" looking for him in the mall and tells him to split. Without him being there, the T-1000 would have found John and assassinated him before the T-800 was able to locate him.
- In The Third Man, the chillingly evil Harry Lime is at the center of the plot but appears for less than 10 minutes on screen. Orson Welles plays him as just a normal guy you wouldn't look twice at, and takes three seconds in a search-light and a somewhat sheepish 'you caught me' grin to completely upstage Joseph Cotten's excellent performance and steal the film.
- In To All the Boys I've Loved Before, the college boy that Gen dumps Peter for is never seen on screen but he is the reason for the Operation: Jealousy plan Peter makes with Lara Jean. And if it wasn't for him, Peter and Lara Jean would not have had the chance to develop real feelings for each other.
- In Top Gun, It's because of Cougar's Heroic BSoD in the beginning that Maverick and Goose get to go to Top Gun.
- TRON Dr. Lora Baines (later, Dr. Lora Baines-Bradley) is on screen for less than ten minutes in the first film, and is Sequel Non-Entity in both canons (TRON 2.0 kills her off, TRON: Legacy canon effectively exiles her in Washington DC). However? She co-invented the laser that gets the protagonists to Cyberspace. She's the one who convinces Alan to warn Flynn, she's the one who solidifies them into a Power Trio and comes up with the plan to break into Encom. Oh, and she wrote Yori, who is this trope in her own right (designing, building, and piloting the Solar Sailer, using her connection to Dumont to get Tron access to the tower, etc.)
- Both the fugitive at the beginning of Vertigo and the policeman that ended up falling to his death are huge factors to Scottie's fear of heights throughout the film. If not for these two unnamed characters, the entire third act of the movie would have been averted.
- WarGames: The missile crewmen played by John Spencer and Michael Madsen in the beginning. It is due to their disagreement during the opening simulation that NORAD decides to replace the missile crews with the WOPR system.
- The Comedian in Watchmen, just as in the original graphic novel. He dies in the very first scene, and only appears in a few flashbacks afterward—but his death kicks off the entire plot, as Rorschach's investigation into his murder leads to the revelation that he was killed by Ozymandias after discovering his twisted plot to end the Cold War. Notably, Jeffrey Dean Morgan nearly turned down the role for this reason, not wanting to play a character who spent most of the movie dead; his agent convinced him to reconsider, pointing out that (much like Khan in Star Trek II: The Wrath of Khan) the Comedian's presence hangs over the entire movie, even when he's not onscreen.
- The Wicked Witch of the West appears onscreen for only about nine minutes of the 101-minute runtime of The Wizard of Oz (with Margaret Hamilton's other character, Miss Gulch, appearing for about three minutes). And yet she is without question the character in the film who has had the greatest impact on popular culture, being remembered as one of the most frightening villains in movie history, and is the Trope Codifier for the Wicked Witch. Both Wicked and Oz the Great and Powerful are plainly inspired by her portrayal.
- Matthew McConaughey's Mark Hanna from The Wolf of Wall Street only appears in the first half of the film, yet he is one of the main influences to Jordan Belfort to be a ruthless broker and a substance abuser.
- The Navy SEALs in Zero Dark Thirty don't appear until the last 20-30 remaining minutes, yet they are the ones who finally raid Bin Laden's compound. The SEAL who kills the very man barely has any dialogue, has little screen time, and isn't as prominent as his team members.
- There is also Debbie, a young analyst and admirer to Maya's work, who gives the information that Abu Ahmed may have faked his death because his deceased brother looked like him, prompting the CIA to track him and lead to his home: Bin Laden's compound.
