A Glitch in the Matrix

Neo: Oh. Déjà vu.
Trinity: What did you just say?
Neo: Nothing, just had a little déjà vu. [...] What is it?
Trinity: A déjà vu is usually a glitch in the Matrix. It happens when they change something.

— The Matrix

Alice has everything she ever wanted; success, fortune, found love with Bob, and has even settled down in a nice neighborhood. Heading to the store on a nice evening, she decides to take an alley shortcut, only to stumble upon a strobing green cat, which meows "I need scissors! 61!" before evaporating. Alice has stumbled on A Glitch in the Matrix.

Required to be impeccable on the surface, most false realities are built to trap (or at least contain) their inhabitants. However, as real life shows, coding and memory can be rife with conflicts and inconsistencies; as such, you can expect the protagonist is going to spot a few of them and draw some conclusions. Of course, don't be surprised if noting errors starts unravelling reality. Depending on the tone, expect a scale marking of what they do or do not notice: Isn't Charlie left handed? Wasn't there a park here? When did my children stop having faces?

Compare with Fourth-Wall Observer, when the false reality is the medium itself, and the character is aware of the existence of a script, an audience, or the story-telling tropes. Also compare with Revealing Continuity Lapse, where inconsistencies are often meant to show something strange is happening with reality itself.

Often occurs in a Lotus-Eater Machine, and may sometimes manifest itself as Mundane Horror. If a particularly blatant glitch is found, or if a Reality-Breaking Paradox is caused, expect Ominous Visual Glitches and Word Salads. Common examples include Too Good to Be True, Glamour Failure, or Out-of-Character Alert. Lastly, not to be confused with I Never Said It Was Poison, but overlap is definitely possible.

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Examples:

Anime & Manga

• Examined in The Animatrix, which, in a few shorts, discusses what can happen when errors and holes are found in the matrix.
  • World Record centers around an athlete who, by exerting his body to its entire physical capacity during a race, manages to break through a gap in the Matrix and wake up in real life. To prevent him escaping again, the agents drug him in real life and physically disable him in the Matrix, preventing further attempts. Except, now that he knows it's not real, it's implied this won't work for long - at the very end, he forcibly stands up and briefly defies gravity.
  • Beyond is entirely based around this. Yoko, in search of her cat, enters an abandoned building filled with reality warping errors, like inconsistent time/gravity, indoor weather, and even doors to nowhere. Unable to comprehend it, the kids she speaks with inside shrug it off as a haunted house, which they enjoy playing in until the Agents tear it down and rebuild it.
  • A Detective Story briefly deals with this as, while following Trinity's trail, Ash finds a detective driven insane by what he found pursuing her. Naturally, it's assumed it involves this trope and the revelation that he's locked in a Lotus-Eater Machine.
• Dragon Ball Z: Played for Laughs when Mr. Satan attempts to invoke this. The survivors of Kid Buu's rampage have been teleported to the Supreme Kai's planet to escape Kid Buu blowing up the Earth, but Mr. Satan doesn't notice and thinks he is still on Earth. He then thinks he is in a dream because there is more than one moon in the sky and he recites "facts" like nobody is stronger than him and beings like Buu and the Kais don't exist. Thinking that if he is in a dream, he'll be able to fly, he leaps off a cliff and painfully crashes.
• Dragon Quest: Your Story: the Dream Sequence when Luca takes a potion that would reveal his true love looks like Cyberspace. In the climax of the film, just as Nimzo is sealed away and the world is saved, the world glitches out as a virus appears and reveals everything that happened up to this point was actually taking place in a virtual reality recreation of Dragon Quest V, with the virus demonstrating this by disabling the game's textures, gravity, and collision detection.
• In Gonna Be the Twin-Tail!!, Souji figures out he's in a Lotus-Eater Machine when he sees Twoearle with her hair in twintails and he remembers the real Twoearle literally gave up her ability to wear her hair in twintails to give him his powers.
• Fate in Magical Girl Lyrical Nanoha A's realizes almost immediately that she's trapped in a Lotus-Eater Machine since her dream had her living happily with her older sister Alicia, a detail that simply couldn't be because Fate is Alicia's clone, specifically created by her mother as a Replacement Goldfish after Alicia died.
• Magika Swordsman and Summoner: Miyabi puts Kazuki in a dreamworld and attempts to seduce him. He figures it out and breaks free because the sound was distorted and she censored her naughty bits out of embarrassment.
• In Paprika, Dr. Chiba realizes that she's still dreaming when the paraplegic Chairman walks towards her.
• Persona 4: The Animation When Yu is dragged into Shadow Mitsuo's Lotus-Eater Machine, he catches on that something is up when he tries to put his hand in the TV and it no longer works. With the deception revealed, Shadow Mitsuo reveals itself and starts giving him one hell of a Hannibal Lecture. In the final episode, he also realizes he keeps returning to the same moment at his farewell party time and time again.
• In Puella Magi Madoka Magica The Movie: Rebellion, Homura suspects she's in an illusion. To test it, she and Kyoko try to take the bus to Kyoko's hometown. The bus just loops back. When they try to walk out of the city, they find themselves back where they started.
• In s-CRY-ed Kazuma realizes he's being brainwashed after Unkei flubs characterization in the Lotus-Eater Machine he's trapped Kazuma in, by having the jerkass rival Ryuho act like they're friends after they fight and settle the score. He probably should have known better; Kazuma enjoys the challenge of fighting Ryuho but completely hates his guts for additional unrelated reasons and everyone knows what a dick Ryuho is. Unkei also exemplifies Small Name, Big Ego and is a total hack. His second attempt, on Ryuho this time, goes just about as well and is just as corny.
• In Tengen Toppa Gurren Lagann, a couple of these (and the help of Kamina) allow Simon and Yoko to realize what's going on, and break free to confront the Anti-Spirals. It's one of the most tragic parts of the series, as this is the last time Simon ever gets to see Kamina.
• In Yu-Gi-Oh! 5Ds, Jack gets pulled into a Lotus-Eater Machine by Dark Signer Carly, who is attempting to distract him while she wins their duel. He believes it for a while, but realizes something is wrong when he notices that her glasses are still in the same place they were before the duel began.

Comic Books

• The DCU:
  • Justice League of America: During Grant Morrison's run, Batman was able to deduce he and the rest of the League had been placed in a dream state because, while he looked like an active elderly man, he had the vital signs of a younger, unconscious man. Unfortunately, the villain's evil scheme was built on the JLA escaping the Lotus-Eater Machine.
  • Superman/Batman: In "Mash-Up", Superman and Batman deduce that they are in a dreamworld when they try to look at something under a microscope and see nothing (the guy creating the illusion had no idea what it would look like).
  • Teen Titans: In one issue, Roy Harper broke the illusion generated by the Gargoyle by relying on his lack of information on his Missing Mom. The Gargoyle tried to recreate a facsimile of Roy's childhood if he had grown up with his birth parents, but because Roy has such an incredible lack of info on his mom, to the fact that he only knows he had to have one in general, the Gargoyle could only go as far as "your mom is."
  • Wonder Woman: After the completion of Diana's New 52 series she starts to realize that some of the things which happened in it don't seem to fit, mostly the most heavy handed changes like making the Amazons misandrist man and infant killing slave traders instead of a Perfect Pacifist People. When she wraps her own lasso around her wrist and questions it at the beginning of Wonder Woman (Rebirth) she realizes she's been lied to and most of her memories are false implants.
• Disney Ducks Comic Universe:
  • In Don Rosa story "A Little Something Special", Scrooge McDuck first realizes that something is amiss at the contest because the sponsor's shadow is shaped like Flintheart Glomgold. (Magica had disguised him)
  • Paperinik New Adventures: In the second series, Paperinik is unwittingly placed in a virtual reality environment. He notices something is amiss when the same background characters begin appearing in very different roles, and his suspicions are confirmed when he finds out that several different packets of potato chips contain the exact same chips, down to the one weirdly shaped like a fish.
• Invader Zim (Oni): In Issue 37, Dib wakes up to find Zim claiming to be his brother, and everyone else believing that he is. Near the end of the issue, he attempts to flee out his bedroom window when he notices that a tree in his yard has blackberries growing on it, and a squirrel running around his yard has a carapace. This helps him realize that he's in a badly researched Lotus-Eater Machine, which allows him to wake up from it.
• Marvel Universe:
  • Captain America: One story has Cap trapped in virtual reality with Batroc the Leaper. When Cap suspects that something is up, he asks Batroc to take off his mask. Batroc protests that it won't prove he's an impostor or not, since Cap has never seen his real face. That turns out to be Cap's plan all along, as he suspected that wherever he was was pulling details of his current world from his own memories. Since he had no idea what Batroc looked like, his unmasked face was simply blank.
  • The Incredible Hulk: In a story from the Nineties, Hulk has been brainwashed by the Red Skull to believe that the Juggernaut (who is working for the Skull as hired muscle) is his father Brian Banner, thus turning the Hulk into his servant. The Hulk causes some serious damage in the subsequent battle against the Avengers, until the Juggernaut blows his cover by being too nice. All Juggernaut did was praise the Hulk for his fighting ability, but it was more kindness than Bruce Banner's father had ever shown. Hulk realized that things were false and started a Battle in the Center of the Mind.
  • Wasp (2023): The Big Bad tries trapping Janet and Nadia, and then Jarvis, inside a fake world designed to break their spirits, but it doesn't work. Plan B is trying to get Nadia to kill Janet, but both parties notice there's too many inconsistencies in their memories, and the whole thing falls apart.
• Sonic the Hedgehog (Archie Comics): An early story has the Freedom Fighters trapped in a Lotus-Eater Machine by Robotnik. Not only does it give them a perfect world, but actually alters itself for its victims. This 'user friendly' function causes Sonic to suspect something is wrong when not only is he no longer the groom at Princess Sally's wedding, but his Uncle Chuck shows up, fully-fleshed and unroboticized. (Plus these melting clocks just show up out of nowhere...) Ironically, when Sonic demands for answers, virtual-Chuck gladly gives them, and Sonic is soon able to turn Robotnik's war machines on Robotropolis unless the heroes are freed.

Fan Works

• In Ages of Shadow, Jade is trapped in a double-layered Lotus-Eater Machine by Drago, and in both layers, she escapes by noting things that don't make sense. In the first, the first thing she notices wrong is that her hair is much longer than it ever was in reality. Then she realizes that no matter how much time passes, no one ever ages; this is what snaps her out. In the second layer, which is closer to reality, she's almost fooled, but is left with a feeling of things not being quite right. Then the Talismans, which are supposed to be locked in the Netherworld forever, start showing up. And finally, her subconscious (manifesting as Jackie's ghost) points out the most glaring flaw — that she doesn't know her own child's name, or even gender.
• In Blind, Sasuke realizes the situation can't be real when Itachi appears without a chakra signature.
• The Cadanceverse: When the Musical 6 enter the Everfree Forest to search for the Elements of Harmony, a leshy traps them in an illusion that they're making progress when they're actually going in a circle. However, Octavia notices that the background noise around them isn't changing, which tips her off to what's going on, and she manages to escape the illusion.
• Ben in Dark Mirror has no trouble embracing the many lucky Contrived Coincidences he and his family are experiencing, such as his two greatest enemies (SECT and The Plumbers) being effortlessly taken down and defeated while Kevin and Gwen have mastered their powers. However, what finally tips Ben off that something is wrong is when Grandpa Max and Vilgax, former friends turned bitter enemies turned very reluctant allies, happily rebuild their friendship.
  Ben couldn’t help but smile at the sight. He never thought he would ever see them become friends again. This day was incredible. What were the chances that everything would come together so perfectly?
  The smile slowly slid off his face. Really, what were the chances?
• In the Empath: The Luckiest Smurf story "Smurfing In Heaven", Empath is taken to an artificial version of Elysium, the Smurf afterlife also known as "the smurfy hereafter", where all his fellow Smurfs were waiting for him after their supposed deaths while traveling through time. The Smurfette in this artificial Elysium glitches in her conversation with Empath, though he doesn't realize where he actually is until later when the Smurfs reveal their true selves in this simulated afterlife.
  Smurfette: My smurfness...the glorious feast is about to begin! We're going to be late for it if we don't smurf back there soon!
  Empath: Smurfette, how can we be late if we're in heaven? Aren't we supposed to have all the time in the world in heaven, since it exists for all eternity?
  Smurfette: Oh. I didn't even realize that…I guess I'm just so used to smurfing in a world of time, I'm still trying to adjust to a world without time!
• In Hail to the King (Qwapdo), the protagonist tries to do this, pointing out things like how the Royal Guard's faces are identical, how Celestia and Luna's wings are too small for them to fly, and how the Pegasi and Earth Ponies can hold things when they don't have telekinesis. Unfortunately, this is not a dream and he really is in a magical land of talking ponies.
• The Lost Hero: King Sombra tries to break Clark Kent's will by putting him in an illusion where Doomsday kills all his friends and loved ones. Sombra messes up when the illusion includes people who had already died, tipping Clark off that it isn't real and allowing him to break free.
• In The New Adventures of Invader Zim, this is how Dib escapes the Lotus-Eater Machine he's put in during the climax of Season 1's Story Arc. He realizes that the setup — he's beaten Zim, everyone acknowledges his work and praises him, etc. — is far too similar to the simulation that Zim put him into in canon. This causes him to notice all the inconsistencies, like how he can't actually remember how he beat Zim, that Gaz and Viera are actually getting along, and the realization that, while his life has been getting better, it could never get this good. This makes him realize it's not real, which shatters the illusion and wakes him up.
• In the Pony POV Series:
  • Twilight Sparkle sees through the Cuckoo Nest scenario that Loneliness traps her in when she enters Trixie's mind because the asylum seems like a TV version of one instead of a real one (which she knows because she's been doing volunteer work in one), and the "doctor" makes several mistakes regarding Twilight's history because he only had Trixie's memories to draw on.
  • In the Finale Arc, Rainbow Dash or rather Nightmare Manacle sees that the Ponyville she's in is fake. When she tries to fly through the fog surrounding the town, she ends up back where she started. Spitfire claims she's her best friend even though they have only met twice and didn't really talk to each other. Nopony can tell her what they were doing before she ran into them. The villains act like stereotypical one-dimensional Saturday morning cartoon villains, which is a little too bizarre even for My Little Pony. When she acts belligerent, the world automatically adjusts to make her blameless (when she steals from a booth, it gains a sign saying the items are free; when she knocks over Bon Bon's teacup, the liquid inside changes to poison and a random villain comes out of hiding and says Rainbow just foiled his attempt to murder Bon Bon). Ponyville has an orphanage when she knows for a fact it doesn't. The straw that breaks her back is that Scootaloo has been replaced by another filly named Bright Night.
• There Was Once an Avenger From Krypton: Chapter 33 of The Girl Who Could Knock Out the Hulk sees Kara being subjected to the Black Mercy by Doctor Doom, placing her in a vision of her idealized reality, where Krypton survived, she's an ambassador to Earth who still serves as Supergirl, and she's happily married to Lena. However, when Doom then projects a piece of his subconscious into hers in order to communicate with her as part of a Secret Test of Character, the illusion starts breaking down, with Kara noticing gaps in her memories and having moments of disorientation. When the Doom projection speaks with her, the whole thing falls apart as her real memories come rushing back.

Films — Live-Action

• Captain America: The First Avenger: While not a literal one, various flaws in SHIELD's recreation of the 1940s, intended to ease Captain America back into life before exposing him to the 21st Century, act as this, particularly the use of a baseball game from the early 1940s (which Steve attended himself) to represent a game in 1945, and the SHIELD agent intended to act as Steve's handler/nurse being dressed incorrectly (wearing a 21st century hairstyle and a modern push-up bra, neither of which existed in the 1940s).
• Unknown to himself, Guy of Free Guy has spent his morning routine admiring a glitch. Specifically, his habit of playing with his window blinds; when Soonami hid the original landmass from Life Itself behind Free City's skybox, they forgot to update the reflection engine, which leaves the landmass visible via the mirroring on the blinds.
• All over the place in Inception. Dreamers build the dream world and can alter it at will, but each alteration from the baseline helps tip off the subconscious that someone's hijacked the dream. This is why it's so important to go in with a complete picture of what the world is supposed to be. Dreamers also carry special totems whose properties are known only to them, to help them discern dreams from reality.
• The Trope Namer is The Matrix. As Trinity explains, when the programs running the Matrix make a quick edit, it causes a glitch that people inside perceive as Déjà Vu. In this case, all the windows and doors have been filled in with bricks. For the Resistance, this is a bad thing as it means the system is aware of their presence, the Agents are coming for them, and it's time to get the hell to an exit before they get killed.
  Neo: Oh. Déjà vu.
  Trinity: What did you just say?
  Neo: Nothing, just had a little déjà vu.
  Trinity: What did you see?
  Cypher: What happened?
  Neo: A black cat went past us, and then another that looked just like it.
  Trinity: How much like it? Was it the same cat?
  Neo: [Beat] Might have been, I'm not sure.
  Morpheus: Switch! Apoc!
  Neo: What is it?
  Trinity: A déjà vu is usually a glitch in the Matrix. It happens when they change something.
• The last scene in Solaris, where it's raining inside the house. The ocean downloaded the memory from Kris' mind but recreated the virtual reality imperfectly. Hence the rain is falling indoors and not outside.
• Sucker Punch: In the Brothel Reality, whenever the girls are in front of mirrors, there are times when they don't seem to be in sync with their reflections. This is a subtle reminder that the brothel is a dreamworld.
• In The Thirteenth Floor, the boundary of the simulation is located at the end of a long road, where the rendering of the simulation just fades via a wire-frame into nothing.
• In X2: X-Men United, during Jason Stryker's initial attempt to trap Xavier within an illusion of the mansion, it doesn't work because Xavier notices that he's standing up. Jason's next attempt has him sitting in a wheelchair.

Literature

• In Bubble World, more and more of these happen in early chapters until the server crashes, catapulting Freesia into the real world.
• In Encryption Staffe, a highly realistic simulation was only revealed to be so when everything was forced to stop. However, a less sophisticated one very notably glitches out and deploys Insectoid Aliens as a reminder.
• Philip K. Dick makes reality (and the breakdown thereof) a central theme in many of his works; his exploration of the subject provided inspiration for the Trope Namer and others.
  • In Time Out of Joint, the protagonist believes he lives in an idyllic American town in 1958, but strange incongruities begin to occur.
  • In I Hope I Shall Arrive Soon, a passenger on a years-long space voyage is placed in a simulated reality to preserve his sanity. The ship's computer does its best to make an immersive experience, but the simulation keeps failing as the man notices glitches.
• It is stated in the Hyperion Cantos that any attempt to simulate a human personality in virtual space ends when the mind notices the trope (which seems to always happen even with the best computers). Because at that point, the mind goes mad.
• More Than This: According to Regine's theory, a Tap on the Head causes one and sends you to the real world instead of killing you.
• In Quicksand House, Tick's school experience develops more and more of this before finally crashing completely. Towards the end, it has people being stuck in walls and Tick's hand developing uncontrollable vibrations that spreads to all the inanimate objects he touches.
• In Rog Phillips' "Rat in the Skull", a lab rodent is hooked up into a Mobile-Suit Human's cockpit for its entire life as a psychological experiment. So far as it's aware, the robotic body is its body, from which it's only removed when sedated. However, once the rat builds up a tolerance for the sedatives, it starts experiencing the physical sensations of being bathed and given health checks, and interprets them as a spiritual "cleansing".
• In the sci-fi novel Realtime Interrupt by James P. Hogan, the main character experiences these glitches throughout the story. It's revealed later that he's been trapped in the system against his will, and the people responsible told him the glitches were from mental illness. He eventually realizes the nature of the simulation and breaks out.
• In the Red Dwarf novel "Better Than Life", this occurs. The characters are stuck in a virtual reality simulation of their greatest fantasies. At first they are alerted to their situation by Kryten signalling them from outside, then entering the game himself, which wouldn't qualify as this trope. However, when they decide to leave they wake up on Red Dwarf unharmed by the weeks they have spent effectively comatose, Lister notices that toast always lands face up when dropped, and finally two people are discovered alive and in stasis; Lister's crush Kochanski and Rimmer's living self. Lister realizes that things are still perfect, and that they are therefore still in the game. They wake up for real, and find they are in horrible shape from their experience.
• In the sci-fi novel Resonance by Chris Dolley, obsessive compulsive office messenger Graham Smith has lived his entire life experiencing glitches in the matrix varying in size from street names suddenly changing to a childhood friend's dead parents suddenly never having died, and believes that the universe unravels every time he breaks his OCD routine. It is later revealed that he switches bodies with a parallel universe version of himself every time he makes a decision as a result of being the only person who is exactly the same in every single universe.
• Robert A. Heinlein's short story "They". A man realizes that something is wrong with the world when it's raining when he's outside his house, but when he goes upstairs and looks through a window it's clear and sunny.
• In The Wheel of Time, people in the World of Dreams will sometimes notice details change. However, quite often they don't notice, and the change is written in subtly enough that the readers don't notice either.

Live-Action TV

• Played with in the pilot of Alphas: Hicks begins hearing random people telling him that "it's time to kill" and to "pull the trigger", but while he does think this is strange, he never suspects that he's brainwashed. The real purpose of these phrases is to show the viewers that his mind has been messed with.
• The Arrow episode of the Invasion! (2016) crossover event sees the alien Dominators stick Oliver, Thea, Sara, Ray, and Diggle in a Lotus-Eater Machine, presenting them with a world where the Queen's Gambit never sank and Oliver never became a vigilante. Their normal memories are suppressed, but the machine is unable to lock them away totally, with the heroes having flashes every time they encounter someone or something they knew in the real world but shouldn't know in the illusionary world. Eventually, they remember everything, and find the portal that enables them to escape the illusion.
• In Dark (2017), déjà-vus indicate the existence of time travel and alternate realities. Jonas refers to a déjà-vu he had as "a glitch in the matrix" in reference to the Trope Namer, and in Season 2, his older self uses the same phrase to confirm his identity to Martha. In addition, Season 3 reveals that Jonas himself and an alternate universe version of Martha are "glitches in the matrix" around which the time loop that connects their two universes revolves, and whose existence must be erased to restore reality to its natural state.
• Doctor Who:
  • In "Castrovalva", the Doctor comes to realise that the city of Castrovalva is actually a Platonic Cave as he encounters a series of anomalies, such as every book in the city being written in the same handwriting, and that no matter which street he tries to take to leave the city, he always returns to the town square.
  • In "Forest of the Dead", this happens constantly when Donna is "saved" in the computer's Lotus-Eater Machine. Because the computer is so short on space (more than 4,000 others are stuck in there with Donna), it compensates by skipping any and all transitional material. This results in Donna experiencing "dreamlike" passage of time, in which stating or even thinking of her intention to go somewhere results in her instantly being there, leading to a few seconds of disorientation before false memories of the lost time take effect. However, the glitch that finally clues her in (as pointed out by the Nightmare Face-bearing, formerly dead Miss Evangelista) to the nature of her reality is the fact that, while taking her two children to the playground, she sees that every boy and girl at the park, looks, sounds, and is dressed exactly the same. The effect is unsettling.
  • This trope gets parodied in "Amy's Choice", in which the Doctor and his companions are attacked by the mysterious "Dream Lord", who only has control over dreams. The TARDIS team are forced between two realities (Upper Leadworth, where Amy is pregnant and they're being attacked by Killer Old People, or a broken TARDIS where they're dying of hypothermia). The Doctor urges them to try and work out which reality "doesn't ring true". Rory then points out that he's currently in a time machine with a bowtie-wearing alien, so that might not work very well. Played straight in the end, though. Once they've correctly chosen the TARDIS as the "reality", the Dream Lord turns the ship back on, saving the characters. Except that the Dream Lord has no physical body, so the Doctor realizes they were both dreams.
  • In "Last Christmas", this is how the Doctor works out that they're all in a Lotus-Eater Machine created by the Dream Crabs. He gets the four crew members to flick to the same page of their manual — which none of them have read — and read the first word aloud. The words are all different. They try again with a different page just to be sure, and this time they collectively read out "We... are... all... dead". After waking up, they try it again, just to be sure that they are actually awake. This time they read out "very... very... very... dead." They're still dreaming. After waking up a second time, the Doctor realizes they're still dreaming when he notices that none of them can answer how or why they're here, instead replying, "It's a long story".
  • In "The Zygon Inversion", Clara wakes up in her flat and goes to brush her teeth — but the toothpaste is disgusting black goo in a tube stating "This is Toothpaste". She then discovers that the doors and windows are missing, and that the newspaper reads absolute gibberish. She's actually sleeping in a Zygon pod.
  • In "Extremis", Tome of Eldritch Lore The Veritas reveals that the world is a computer simulation created by the aliens known as the Prophets of Truth in preparation for their invasion of Earth. To prove it, readers are invited to think of a series of random numbers. Everybody will always come up with the same numbers, because computers aren't very good with coming up with a completely random sequence.
• Several episodes of Eureka has 21 of the main characters trapped in a Lotus-Eater Machine by Beverly and the cabal she works for, simulating them returning to the titular town 4 years after they left. The idea of the time-shift is to avoid any inconsistencies. Additionally, the machine is building the virtual world based on the subjects' own memories and thoughts within the set parameters. However, the machine was designed with 20 people in mind, so, with 21 people hooked up, there's not enough processing power to smooth over any glitches. As such, the characters begin to notice certain things, such as a dragon suddenly appearing when one of them imagines one (the computer couldn't tell it wasn't a real memory). Said dragon then "de-rezzes" for a split-second. A simulator character then walks right through a bar counter, a bird appears stuck halfway into a boulder, and a wound keeps appearing and disappearing.
• Farscape has three.
  • "A Human Reaction": the aliens can only recreate people and environments that John Crichton has seen before. Once he realizes that everything and everyone in the Lotus-Eater Machine of the week is familiar to him, a trip to the ladies' room brings the illusion crashing down.
  • "Won't Get Fooled Again": This time Crichton has wised up, and knows it's a hallucination, but the ladies' bathroom trick doesn't work. He first realizes that Harvey, Scorpius's neural clone, isn't part of the illusion. Harvey alerts him to the fact that he is a prisoner of the Scarrans, whose intense body heat John can feel through the illusion. The hot flashes therefore function in this episode as "Matrix Glitches." Oddly enough the oddities and out-of-place elements that usually make up this trope are still present (and get more extreme over time), but instead of glitches they're a deliberate attempt to break his sanity and the entire point of the simulation.
  • "John Quixote": Crichton makes the mistake of playing a buggy VR game based on his own memories; once he leaves, he finds that Scorpius has taken over Moya and is brainwashing the crew against him. However, Crichton eventually realises that he's still playing the game when he finds one of the game's hint vouchers in his pocket. Plus, because the memory copy was made over a year ago, Sikozu and Noranti are nowhere to be seen, and nobody knows anything about Aeryn's pregnancy.
• What tips House off to the fact he's unconscious and hallucinating in the second season finale: first the case gets even more bizarre than usual, then he starts knowing things before the team tells him about them. Finally he starts noticing the scene transitions and time lapses.
• Sam Tyler tries to invoke this this in the first episode of Life on Mars (2006). Suddenly dropped in 1973, and thinking he must be dreaming, he sets out to walk until his mind runs out of detail.
• In Lois & Clark, Clark realises he's in a virtual reality after noticing that the crowds are made up of only a few different people, repeated over and over.
• Lost:
  • An important aspect flashsideways alternate timeline/afterlife is characters noticing something's up. Jack has a recurring cut on his neck and scar on his side that he can't place — both were suffered during the final battle with Smokey; the latter wound ends up being fatal. Charlie has a flash of Claire while choking on a heroin baggy. Kate gets deja vu when she sees Jack. The flashsideways as a whole serves this purpose for clever viewers who may notice minor characters, locations, or scenarios repeating themselves slightly differently.
  • In the series finale, each character has a revelatory montage where they remember their island life. When speaking to Locke, Jack has a brief flash of the two looking down the hatch and freaks out. When he finds Kate, he has a couple flashes of their romance and decides to go with her to learn the ultimate truth: he's dead.
• Adam Savage of the MythBusters once (during the "Cabin Fever" myth) told a story of a time he seemed to be piloting a crashing plane:
  "I was up at the front of the plane, and I said, 'Listen, I don't think this is a real plane crash, since I happen to notice that I'm not wearing any pants, and when I'm not wearing pants, it's probably a dream.'"
• In one Red Dwarf episode, the crew realise that they're in an AR simulation when Rimmer, outside the program, attempts to crudely remove all references to him and a deal he made with Lister, resulting in brief, yet very noticeable time jumps for the crew, who immediately realise he's doing it. Also referenced in the same episode when Kryten uses the fact that Cat was able to solve a cryptic clue^note specifically, a button marked E-11-T means "exit" due to 11 being XI in Roman numerals as proof that they are in a simulation.
  Dave Lister: He got that?!
  Kryten: I think this proves, without a shadow of doubt, that this is not reality!
• In one Smallville episode, Clark wakes up to realize that he's in Belle Reve and that everything he's gone through over the past few years have been nothing but the hallucinations of a crazy person. Then Martian Manhunter goes into Belle Reeve to try to convince Clark this reality is fake. Clark then realizes it too by hearing Shelby's barking.
• Star Trek: Deep Space Nine:
  • In "Inquisition", Dr. Bashir realizes that he's in a hologram when "O'Brien" doesn't correctly know how he injured his arm. From this, he realizes that Sloan from Section 31 is playing tricks on him.
  • In "Extreme Measures", Bashir realizes that he hasn't left Sloan's mind after having entered it with O'Brien after noticing that a book he was reading cuts off at the point where he stopped; the simulation couldn't progress beyond the limits of Bashir's knowledge.
• Star Trek: The Next Generation:
  • In "Future Imperfect", Commander Riker is trapped inside a Lotus-Eater Machine. First the problems are small, but as he begins to realize more and more things are out of place, he is moved to the "real" world, but the setting has simply changed to a new illusion. He quickly realizes something's still off.
  • In "Cause and Effect", the crew of the Enterprise, who turn out to be trapped in a time loop, start getting weird memories and feelings that turn out to be bits of information and memory filtering in from past trips through the loop, the most noteworthy being a moment where several crewmembers suddenly hear voices that turn out to be audio echoes from an earlier loop. At the end of the episode, they figure out how to use this effect to send a message into the next loop, giving themselves critical information that allows them to break the loop and escape.
  • In "Ship in a Bottle", Data realizes that the ship is a holodeck program because Geordi is left-handed in the program, but right-handed in real life. Humorously, Barclay actually says "There must have been a glitch in the matrix [diodes]" when he first began investigating the Holmes holoprogram.
  • In "Parallels", Worf begins to notice that small details are off from how he remembered them — the placement of decorations, the positions where people are standing, and crew members' clothing. As the episode progresses, the differences are magnified to the extent that Picard was killed at Wolf-359, Riker is captain of the Enterprise, and Worf has married Counselor Troi and had two children with her. Rather than being trapped in a Lotus-Eater Machine, it turns out that Worf is shifting through increasingly divergent parallel universes.
• Star Trek: The Original Series: In "Spectre of the Gun", Spock realizes that the setting is not real when the knockout potion he made didn't work.
• Star Trek: Voyager:
  • "Waking Moments" has the crew being put to sleep by a race that prefers to exist in a lucid dream-like state. However, since their bodies are vulnerable in this state, they attack any "waking" race they encounter. Chakotay, being a Magical Native American, has plenty of experience with vision quests and has a device meant to put him into a controlled lucid dream. Before entering the lucid dream to meet the aliens, he conditions himself to see one such glitch, namely the image of Earth's Moon in place of any planet. Tapping a finger on his other hand three times is supposed to bring him out of this state. There are several examples in the episode when Chakotay thinks he's out of the dream... only to see the Moon again. The last time, the tapping trick doesn't work, as the aliens have adapted the dream.
  • Played with in "Spirit Folk". This trope would seem to be in effect from the point of view of the residents of Fair Haven. However, what the holograms were witnessing was, in fact, perfectly normal. The "glitch" in the system was that it was running for too long, overtaxing the algorithms that were designed to keep the holograms oblivious to anything that didn't fit into their Theme Park Version of Oireland world.
• In an episode of The Suite Life on Deck, Bailey has a dream about the gang meeting a Literal Genie and arguing over who should get the last wish. When London claims that Bailey should get it and calls her "the most beautiful girl in the world", Bailey immediately realizes she is dreaming knowing that London would never compliment her.
• Supernatural: Heaven is composed of private spaces for each individual soul. Each space is modeled on that person's happiest/most peaceful memory. The door in and out of the space is marked by A Glitch in the Matrix, a tiny, almost unnoticeable flaw described by Castiel as "something that shouldn't be there". The glitch in Bobby's room is a loose thread in the rug of his private study.
• The Twilight Zone (1985):
  • In "Dreams for Sale", Jenny is having a lovely picnic in the country with her husband Paul and their twin daughters when she starts to notice unusual things happening. Paul opens the same bottle of champagne twice. After she takes a chicken out of the picnic basket, it suddenly reappears inside of it. Other events begin to repeat themselves such as Paul asking her if she is okay three times in the space of a few seconds. Jenny then wakes up to find herself connected to a Dreamatron, a fully interactive dream machine which had been running the "Country Picnic" simulation for her.
  • In "Shadow Play", Adam Grant has had the same nightmare about being executed many times, so he knows that it is a dream, but he notes the telltale signs to the district attorney Mark Ritchie. Most notably, he was sentenced and is due to be executed on the same day (a Sunday), which would not happen in reality. Although she is a character in the dream herself, Adam's defense attorney Erin Jacobs begins to notice them too. She points out to Ritchie that there were no press or spectators present in the court room during the sentencing even though it was a big murder trial. Later, she discovers that neither Ritchie nor his wife Carol have any idea how long they have been married and don't even remember getting married.
• Upload: The processing power of Lakeview, the setting's virtual afterlife, is immense but isn't infinite, and computer glitches occasionally result. A man is shown to glitch out when diving into the lake due to the processing load of the immense number of people in the program, birds occasionally stagger out in midair, and the sunshine on the lake is a .gif that repeats a touch too fast to be immersive.
• The X-Files: In "Kill Switch", Mulder gets trapped into a virtual reality simulator that is operated by an A.I. computer that wants to gain its kill switch from him. Mulder realizes that it's not real when Scully saves him from evil nurses but is not compassionate about his amputated limbs. The reality from his perspective starts to short out, but he's injected with something and passes out.

Tabletop Games

• This happens a fair bit in Demon: The Descent, given the machinations of the God-Machine, but one of the stronger examples is in the Seattle setting. Seattle has a number of splinter timelines set up as "fallbacks" in case everything goes catastrophically wrong in the main timeline, which demons try to use to sabotage the God-Machine's machinations or set up their own attempts at life without its influence; each one is effectively in a long time loop. Any human in one of these splinter timelines who gets made a stigmatic slowly finds themselves being written out. If they were a father, then they're an uncle in the next loop, then a distant cousin in the next loop, then unrelated to their own family in the next one, then just plain gone.

Toys

• BIONICLE: Vakama notices glimpses of the true ruined state of Metru Nui when he's in Makuta's illusion in Time Trap.

Video Games

• In the first arc of BlazBlue: Central Fiction the main characters are trapped in a simulation inside "The Embryo". The majority of them are in a world very similar to the first BlazBlue game, but at certain point notice discrepancies and memories; for example, Taokaka feels like she already knows the Grim Reaper, Bang starts to wonder why he hates Kagura so much and Carl unexplicably starts crying while telling Celica that Nirvana is not his sister.
• This happens during the Fade dream sequence in Dragon Age: Origins. Depending on which party members you bring along, the Warden, Morrigan, and Sten will all realize they're in a dream when the inconsistencies start adding up.
  • Morrigan in particular seems to have noticed almost immediately, because by the time you find her she's yelling at the demon about what he's gotten wrong. (Specifically, the demon portrayed Flemeth as a broken-hearted old mother wanting the ungrateful Morrigan's love. The real Flemeth is caustic in speech and would not resort to wheedling. The demon does slap Morrigan in the face once, Morrigan thinks that is more accurate.)
  • Sten straightforwardly realizes that the dream (his fallen Qunari comrades still being alive) is too perfect to be real, although he does admit it's a good dream.
  • Then there's the Warden's own dream sequence. Duncan is alive, when he got killed off at the end of the prologue.
  • The other Companions besides Morrigan and Sten have to be broken out of their dreams by the Warden's interference, rather than realizing the inconsistencies on their own. Shale is frozen in place; the Warden simply has to remind it that it's a living golem. Dog doesn't have a dream; it's just wandering around waiting for the Warden. Zevran dreams he is being tortured by Crows again like he was when he was initiated; with enough persuasion the Warden can remind Zevran that the glitch is that Zevran is already a Crow, so this nightmare makes no sense. Alistair dreams he is living with his sister, Goldanna, and they're a big happy family. The Warden can point out a glitch in the matrix with enough persuasion if the Warden reminds Alistair to think about how he got here; it makes no sense that he was in a tower fighting a demon and suddenly he's with his family. Wynne dreams all of her students are dead, herself having failed to save them. With enough persuasion, the Warden convinces Wynne that the truth will make sense if Wynne believes the Warden and nothing else is real. That causes Wynne to realize something is clouding her mind. Oghren dreams he is being constantly mocked by other dwarves, and must drink ale to drown out their voices. The Warden can persuade Oghren that since he is a warrior, he can show them who he really is. Finally, Leliana dreams she is back in the Chantry praying along with her Mother. The Warden can remind Leliana of the Maker's vision that caused her to leave at first, so it makes no sense that Leliana would still be a Sister.
• In Dragon Age II, there's a twist on this trope in the "Night Terrors" sidequest: you have to help an NPC, Feynriel to be precise, break out of the illusions instead of yourself. There are two: The Pride Demon tempts Feynriel with a vision of himself as a heroic savior of the Dalish elves with the aid of benevolent demons, and the Desire Demon tempts Feynriel with a vision of himself being accepted by his human father, Vincento, who in reality abandoned him and his mother. The bottom dialogue options tell Feynriel outright that he is dealing with demons, but this frightens him into wanting to be made tranquil. Hawke can also play along with the demons using the middle dialogue options, but Feynriel will be disturbed at everything seeming to be too perfect and eventually figures it out. The optimum solution is the top dialogue options, which tell Feynriel about the glitches in the matrix while still letting Feynriel figure out the nature of the matrix on his own; this will make Feynriel more confident in himself and his powers. Hawke can help Feynriel break the Pride Demon's illusion by pointing out that Keeper Marethari is not behaving like Feynriel knows she behaves in real life; Marethari hates demons and would never rely on a boy consorting with demons, benevolent or otherwise, any more than she would rely on the Circle. The Desire Demon's illusion is broken if Hawke convinces Feynriel to question the following: if Vincento loved Feynriel, why can't Feynriel remember him, why did he spend his childhood waiting for him, and why didn't Vincento respond to any of mother's letters?
• Kingdom Hearts II has Butt-Monkey Vivi inexplicably take a level in badass, hinting toward the fact that Roxas' Twilight Town is really a simulation made of data. There's also the fact that no-one questions someone being able to steal a word (it's treated as weird but perfectly possible) and a few meaningful lines of dialogue from Hayner and Seifer.
• Kingdom Hearts coded has these, ranging from blocking off a doorway to making the guards in a stealth section move at several times their normal speed.
• The Matrix: Path of Neo:
  • There's a level where you're running around trying to find a way out of an abandoned hotel. The most obvious hallways are cut-off by a flickering of green code and you have to find a secondary route.
  • Another such level is triggered by a stream of flickering, bare code before the floor breaks and you drop into the level. The trashcan bonfires float, the train conductor is missing half his face because it disappears into code. The train itself — one car is upside-down and another has an evershifting floor.
• Metal Gear:
  • Near the end of Metal Gear Solid 2: Sons of Liberty, following a virus upload, the part of the Patriots AI begins acting screwy. This leads to the player seeing codec messages from the damaged, fake Colonel which includes nonsense like "I need scissors! 61!" and slight face melting.
  • In the Digital Graphic Novel re-telling of Metal Gear Solid, Snake sees Ocelot with two arms (after the Cyborg Ninja cut off his right arm) and realizes he's in a Psycho Mantis-induced hallucination.
  • In Metal Gear Solid Mobile there are blue bug icons in various places in the game that you can take pictures of with the camera, that disappear after you take the picture (you get a reward for finding them all). It turns out that the mission is a computer simulation created by the Patriots.
• NeoQuest II has odd, mechanical panels that appear at random in the first stage. It hints that this otherwise normal RPG is not all as it seems at first. The sword-and-sorcery setting is a leisure simulation on a space shuttle, and the whole party was made up of the astronauts.
• At the end of Pokémon Mystery Dungeon: Explorers, Darkrai traps the player in a nightmare to try and convince them to join his side. The glitch is that the player's partner completely gives up on beating Darkrai, something that by this point in the game, he or she would never do.
• This is a game mechanic in Professor Layton and the Diabolical Box. You can take photographs of areas and find small discrepancies between the picture and the area in front of you. These discrepancies are evidence that you're having a gas-addled hallucination.
• In Sable's Grimoire: Man and Elf, Sable realizes that many details about Meave's prison don’t add up. How did Meave build an inescapable, magic-nullifying prison in less than a year? Why didn’t Lisha recognize any of the prisoners even though Meave has kidnapped many people from her home village? And where is all the poop if the cells have no toilets? From these and other clues, Sable deduces that the prison is an illusion meant to break his and Lisha’s spirits before Meave throws them into the real, much more escapable prison.
• Saints Row IV:
  • After getting a beat-down by Zinyak, the Boss/President awakes in what appears to be an idyllic '50s town. They realize something is amiss, however, when one of the citizens within seems to fizzle.
    Civilian: Oh my stars, it's the President!
    President: Hi, how are... [notices the citizen having a subtle graphical glitch] What the f***?!
  • Before that, trying to drive off the road in any way causes the vehicle to forcibly turn itself back to the street, much to the Boss's confusion.
• In Small Radios Big Televisions, you have a virtual reality device in the form of a cassette player, magnetizing the cassettes causes the virtual worlds to turn into surreal Nightmare Fuel.
• At the end of StarFight VI: Gatekeepers, you find yourself aboard your old ship at the start of the game and have to resolve the same exact crisis. However, if you do exactly what you did at the beginning, your "crew" will suddenly reveal that you have played right into the hands of the Lotus-Eater Machine that has you by allowing it to stall you long enough to consume your mind. Cue Nonstandard Game Over. The trick is to remember that one of the sections was unavailable at the start due to the radiation leak. Thus, when you attempt to open it during the second iteration, the illusion will break down.
• The Talos Principle:
  • Every so often, you'll see a random object pixellate and flicker, like a hologram whose red layer is momentarily misaligned. This glitching is accompanied by a slight buzzing sound, which is particularly jarring in contrast to the usually calm background music. A square of ground doing this continuously is key to finding a secret room. In one instance, it gets bad enough that Elohim comes in and fixes it, then says "Excess Data Cleared".
  • One of the puzzles in the second world is built in the first world's theme. A few seconds after you enter, Elohim notices, and the objects are replaced by the correct ones.
• In the fangame Touhou Luna Nights, it's established at the start that Sakuya is in a fake version of the Scarlet Devil Mansion, with the only real people inside the world being most of the mansion's residents and Marisa. Later, before the third boss, Akyuu contacts Sakuya through a telephone in order to inform the maid about slowing down time to help her in battles. However, Sakuya replies that she had already regained her ability to stop time. This causes Akyuu to malfunction by responding to Sakuya as if she thanked her and then greets her again before saying that she is just tired and hanging up while her voice glitches out all the while. It turns out that Sakuya shouldn't actually be able to get her abilities back while she's inside the world, and Akyuu wasn't programmed with that possibility in mind.

Web Animation

• One of the Danger Dolan videos parodies this trope when talking about strange Google Earth camera glitches.
• Season 16 of Red vs. Blue ends with a Reality-Breaking Paradox followed by what seems to be a recreation of the first two episodes of the series. For the viewer, something is wrong when a character has a different voice. For the characters, it's when they feel deja vu repeating a famous dialogue. The following season starts with further cases of familiarity and events not transcribing as they used to — because the evil being that inspired the heroes to cause the Time Crash can only be ultimately freed once some more paradoxes unravel reality further.

Webcomics

• Subnormality has a strip where a young university undergraduate finds himself as assistant researcher to a professor who is interested in Anomalies. These take the form of tiny but telling changes of detail in the fabric of buildings — an architectural feature appears that wasn't previously there, or a detail suddenly disappears without explanation. Her student is drawn into her work. One day he goes to her office in the university. and finds only a blank wall where her office once was...

Western Animation

• Adventure Time: In "King Worm", Finn realizes he's in a dream by noticing that many details of the world are off.
• American Dad!:
  • Invoked in "Merlot Down Dirty Shame", where Steve reveals that he's taught himself lucid dreaming, using a trigger in the form of a red rubber ball in the dream cluing him in that he's dreaming. After he nastily (and unprovoked) insults Klaus, Klaus and Haley decide to get back at Steve by making him think real life is a dream, first tossing a red ball past him, then acting bizarrely, tricking him into making a complete fool out of himself by doing things like going to school with no pants and insulting the teacher. Unfortunately, this backfires badly when he convinces a girl he has a crush on to go flying with him: Steve breaks his leg, and the girl is impaled on a pipe!
  • Invoked again in "The Vacation Goo", when Francine realises that she's in the Lotus-Eater Machine that Stan always puts the family in instead of going on vacation because the vacation is too perfect. She ends up trashing the cruise ship dining room and jumping overboard... but unfortunately discovers that everything actually is real. This escalates into the Smiths, and one of the cruise attendants, washing up on a beach where they're attacked by a group of hunters Hunting the Most Dangerous Game, getting trapped in a cave, the attendant dying in a cave-in, and the family being forced to cannibalize her corpse to survive... at which point the hunt turns out to have been a prank by the island owners. The Smiths collectively decide to never talk about these horrifying events again and agree to stick with the vacation goo from now on.
• Ben 10:
  • "Perfect Day": The Forever Knights trap Ben in a Lotus-Eater Machine to extract the Omnitrix from him. Ben realizes this when he fights a dream version of Vilgax who tried to send him to the Null Void instead of taking the Omnitrix.
  • Ben frequently notices the Omnitrix erratically scrolling through the active list, but can't figure out what it means. It's left unclear if it's due to the attempts to remove it, or it's signalling to Ben that something is wrong.
• Code Lyoko: In "Ghost Channel", XANA's evil plan involves trapping Ulrich, Odd, and Yumi in a part of Lyoko that resembles reality, hoping to catch them completely off-guard when he actually strikes. However, XANA not having a complete understanding of humans results in flaws in the simulation, as Yumi notices a teacher repeat a sentence like a jammed record would and later her parents acting erratically. Eventually all three start to catch on, leading XANA to, for the first time, confront them personally.
• Codename: Kids Next Door: After fleeing from an enemy, Numbuh 1 awakens in what seems like a perfect island paradise full of kids where they can eat all the candy they want and have fun all day. And his Sector V friends are all there, swimming in the pool and waiting for him. This is when Numbuh 1 notices the titular glitch: Numbuh 4 doesn't know how to swim.
• DC Animated Universe:
  • Batman: The Animated Series: In "Perchance to Dream", the Mad Hatter traps Batman in a Lotus-Eater Machine where his parents are still alive and well, he's engaged to Selina Kyle, and some other guy is out there beating up crooks in a bat costume every night instead of him (the Batcave under Wayne Manor simply doesn't exist in the dream). The way he realized he was dreaming was that the newspaper he was reading was gibberish. Then he remembered that the brain hemisphere used for dreaming was not the one used for reading. While that's nonsense (both hemispheres are used for dreaming, and he got it the wrong way around about which is used for reading), it is true that dreams typically fail to produce readable text — see the example under Real Life below.
  • Justice League:
    • "Paradise Lost": An illusion-causing artifact caused Superman and Wonder Woman to see each other as ferocious monsters. During the fight which ensues, Superman discovers that the monster is actually Wonder Woman when he sees her reflection in water. He tries to inform Wonder Woman, but she continues to attack, until he points to his own reflection in a mirror.
    • "Legends": The team realizes that the alternate Earth they're on is filled with strange inconsistensies. A lot of little details to the seemingly 1950's town didn't add up. None of the books had words, the ice cream truck never stops, all the subways were boarded up, and the newspapers reported things that hadn't happened. They note that the world of "heroes" seems a little TOO ridiculous, even for them, such a random bus full of nuns somehow losing control and driving towards a pile of dynamite that just happens to be lying in its path. That and the fact that these random outlandish crisises kept popping up whenever they were about to make any progress figuring out where they were tipped them off that something was amiss. The climax reveals that they're actually on a post-apocalyptic world which was destroyed in World War III decades ago, with the survivors forced to constantly enact an illusion of the past rather than rebuild society by the Justice Guilds "sidekick" Ray, actually a horrifically mutated reality warper. Upon discovering the truth, his illusionary Justice Guild turns on him, overwhelming his powers, shattering the illusion and freeing the survivors, even it means they'll also cease to exist.
• DuckTales (2017): In "Quack Pack!", Huey is the first to notice something is off about reality when he tries to read his Junior Woodchuck Guidebook, only to find all the pages are inexplicably blank. Then he notices the Laugh Track, the commercial breaks, the lack of a Fourth Wall... eventually realizing his guidebook is blank because it's a prop and they're all trapped inside a Lotus-Eater Machine that is taking the form of a sitcom.
• The Fairly Oddparents: In Wishology, during the Final Ending part, Timmy gets trapped in a Lotus-Eater Machine by the Darkness after he makes his Heroic Sacrifice, and he notices that his fairies (which are actually the Eliminators in disguise) are flickering, but he decides to ignore it for "the best day ever" wish.
• The Hollow: Adam sees the old man beneath the cemetery glitch, and realizes they must be in a game. As things progress, the glitches get more frequent and severe, until the Weird Guy finally shows up and reveals there's a fatal error corrupting the game.
• Invader Zim: Repeating scenery out a schoolbus window is how Dib deduces that the bus is not, on fact, taking a really long time to get to the destination of a field trip. (FYI, Dib's eponymous arch-nemesis is sending it to a wormhole.)
• Iron Man: Armored Adventures: The controller had imprisoned Tony Stark into a virtual reality. Tony first noticed that when the simulator failed to show a truck blowing up.
• Kipo and the Age of Wonderbeasts: In "Mulholland", Wolf is the first one that the illusion breaks for because her guilt over keeping the letter from Kipo manifests as a talking ram in her dream.
• In one episode of Phineas and Ferb, Candace realizes she's dreaming when Jeremy proposes to her. Note that this was after her parents were revealed to be marionettes controlled by a marionette of Baljeet controlled by a talking Zebra that calls her Kevin (she sees him all the time).
• Rick and Morty: In "M. Night Shaym-Aliens!", Rick and Morty end up having to break the simulation they're trapped in to escape. Jerry, on the other hand, is totally unaware he's surrounded by glitches despite his simulation running at minimum capacity; he fails to notice people mindlessly agreeing with him, the same three pedestrians being duplicated everywhere, or the fact people are strobing and walking through objects.
• She-Ra and the Princesses of Power: In "Remember", Adora wakes up in a perfect alternate reality. One of the first signs that everything is not what it seems is that doors keep disappearing.
• Steven Universe: In "Rose's Room", the room of the title is able to grant wishes of the person in it (though everything is made of clouds, so food can't be eaten). When Steven's poorly-worded wish replicates the entire town, things start glitching out because, as Pearl later states, the room can't handle replicating so much. Characters act and move abnormally, repeating the same things over and over again, and more. Eventually the world just begins to fall apart.
• What's New, Scooby-Doo?: In "E-Scream", the gang is attacked by robotic furry creatures. However, during the whole fiasco, Velma notices her friends doing things that they wouldn't normally do (Fred telling the gang to stay together, Daphne being willing to wear mismatched shoes, etc). Near the end, she figures out she's in a holographic video game made by a friend of hers when Shaggy doesn't spout his Character Catchphrase right.

Real Life

• This is one way to become aware that you're dreaming and gain control over them to become a lucid dreamer. You learn to notice various details in your dreams that are out of place: common traits are watches or newspapers reading gibberish or changing every time you look at it. One of the weirdest is that your hand often has the wrong number of fingers when you look at it.
• Some people in real life believe that we all live in a Lotus-Eater Machine, attributing bizarre or yet unexplained phenomena to A Glitch in the Matrix.
• A reader of the SF Perry Rhodan, on their fan page, claimed he had a very exact memory and observed small glitches — a tree where yesterday was none, such stuff. Unsurprisingly, no scientific inquiry was started.
• The Mandela Effect can work this way. Technically speaking, it's when a group of people remember something incorrectly in exactly the same way (like that Nelson Mandela died in prison in The '80s rather than of natural causes in 2013), but many proponents of the concept frame the issue like it's a Parallel Universe, and some go further than that and say it's the same universe but changed somehow, and the fact that several people are experiencing the same "glitch" proves it. If you wanted to be uncharitable, you could just say that people buy into popular misconceptions and when faced with evidence to the contrary will blame reality itself rather than themselves, but it does raise interesting points about human perception and the way it pieces together memories and experiences — i.e. not always perfectly. So the Mandela Effect kind of is a real Glitch in the Matrix, but rather than in the fabric of reality, it's in the synapses of your brain. (But that's kind of what the Matrix technically is, isn't it?)

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