-> "I don't drop character 'til I've done the DVD commentary."
--> -- '''Kirk Lazarus''', ''Film/TropicThunder''

This is when a character who is an actor (not an actor in RealLife who plays a character) goes so deep into their role that they end up temporarily forgetting their original self. They usually start MethodActing, and before anyone knows it are so immersed in the role they're playing that they almost literally ''become'' that role, forgetting their old name, life, and setting aside their original personality. It's worth noting that while this is analogous to BecomingTheMask, the character who becomes this is not a criminal or TheMole, may not even ''like'' the role they have immersed themselves in, and has gone so deep into the role that they don't lament any LossOfIdentity or even remember having been a different person (much less compare that life to the present).

While in this state the character may act against their own interests or those of their allies and loved ones, though [[GetAHoldOfYourselfMan a good slap may fix them]], or pushing a BerserkButton their normal self would take issue with. If the character had a previous psychological disorder, this may result in temporary LossOfIdentity or even forming one or more [[SplitPersonality Split Personalities]]. In extreme cases it may take {{Deprogram}}ing to bring them back.

This trope can be considered a mundane, non-[[AppliedPhlebotinum Phlebotinum]] version of getting hit with LaserGuidedAmnesia and having FakeMemories implanted.

A SisterTrope to CannotTellFictionFromReality.

Compare with BecomingTheMask, where con men or TheMole who grow to like their assumed identity more than their original one, and also ThatManIsDead, in which the character emphatically rejects his old identity. Compare also EnforcedMethodActing, where this is imposed on an actor.

Contrast BrainwashedAndCrazy and SplitPersonalityTakeover.
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!!Examples:

[[foldercontrol]]

[[folder: Anime and Manga]]
* In ''Anime/YuGiOhZEXAL'', Fuya Okudaira, a child actor, is pressured by his StageMom to not speak with other children and to focus on his role as D.D. [[PsychicPowers ESPer]] Robin. While Fuya wants to be friends with other kids, he doesn't want to disappoint his mother. Upon coming across a [[ArtifactOfDoom Numbers card]] (which amplifies the user's desires, usually to a sinister extent) that takes a form similar to his mother, he begins to believe that he really is D.D. [[PsychicPowers ESPer]] Robin, and vows to protect his card, No. 83: Galaxy Queen, as he would his own mother.
* In ''Manga/MidoriDays'', Seiji and his {{Delinquent|s}} friends get called upon to play the roles in a movie of the underlings of a character played by Aikawa Shou, their favorite actor. During Shou's tearful death scene, the boys get too worked up, rise up and beat the crap out of the actors playing the guys who killed him. The director decides to ThrowItIn.
* In the anime film ''Anime/PerfectBlue'', Mima confuses scenes from the TV series in which she acts with reality, played for MindScrew.
[[/folder]]

[[folder:ComicBooks]]
* ''Franchise/{{Batman}}''
** Back when SelfDemonstrating/TheJoker had his own comic series in the 1970s, one of the opponents he faced was an actor who had started to believe he actually was Franchise/SherlockHolmes.
** The post-Comicbook/ZeroHour version of the second Two-Face, Paul Sloane, was reimagined as an actor so involved in method acting that he ended up turning himself into one of Franchise/{{Batman}}'s [[ThematicRoguesGallery deformed, psychotic rogues]] while researching a part.
** One of the possible deaths of Batman in ''Comicbook/WhateverHappenedToTheCapedCrusader'' has him trying, and failing, to talk down an actor who got lost in the supervillain part he was hired to play.
* In recent interpretations, Franchise/SpiderMan enemy the Chameleon sometimes has trouble discarding his assumed identities without some mental issues.
* In a 1970s story, a combination of psychological conditioning and PTSD left Creator/MarvelComics super-spy the ComicBook/BlackWidow mentally "stuck" in her cover identity as mousy schoolteacher Nancy Rushman.
* This was part of Judge Doom's backstory in ''[[WhoFramedRogerRabbit Roger Rabbit: The Resurrection of Doom]]'', explaining why nobody knew who he really was until after the events of the movie.
* The Creator/{{Vertigo|Comics}} reboot of ''Series/HumanTarget'' made this a key part of Christopher Chance's success. He was so good at impersonating his clients that he actually built himself into their personalities in order to fool whoever was trying to take a swing at them, and required extensive deprogramming once a job was complete.
* A combination of the Scarecrow's Fear Gas and the mind-altering System lead [[ComicBook/{{Azrael}} Jean-Paul Valley]] to believe that not only was he {{Batman}}, but the one ''true'' Batman, going so far as to claim that he was nothing if he couldn't be Batman.
[[/folder]]

[[folder:Film]]
* This concept is a metaphorical interpretation of ''Film/BlackSwan''. Nina, sweet and a perfect representation of the White Swan, tries so hard to become the Black Swan that she loses herself.
* The 1947 FilmNoir ''A Double Life'' is all about this, where an actor (Ronald Coleman) playing ''Theatre/{{Othello}}'' on Broadway finds his life being taken over by the role and eventually [[spoiler:follows in the part's footsteps when he murders his mistress.]]
* Deconstructed and parodied in ''Film/TropicThunder'' by Robert Downey, Jr.'s character. And yes, that quote at the top of the page is serious too, because Robert Downey Jr. stays in character for the ''actual'' film's DVD commentary (Although this was an [[OverlyLongGag extended joke]] about the character he played).
* According to the sequel comic, Judge Doom of ''Film/WhoFramedRogerRabbit'' was originally [[spoiler:a Toon actor named Baron Von Rotten, who often played villainous roles (a deleted scene of the movie claimed Doom was the one who shot Bambi's mom). A concussion during a shoot led him to think he really was a villain.]]
* In ''Film/BadEducation'' Juan is only pretending to be [[spoiler:his dead brother, Ignacio]]. But in the process, Juan gradually ends up in the exact same situation, such as getting involved with the same men and dressing up as a transvestite.
* In a similar effect like the one in ''Perfect Blue'', Nikki Grace from ''{{Film/Inland Empire}}'' confuses her acting with reality, at a point where is impossible, even for the spectator to tell which is which.
-->'''Nikki:'''Damn... It's sound like dialogue from our script!
-->'''Kingsley:'''Cut, cut it
[[/folder]]

[[folder:Literature]]
* Creator/KurtVonnegut's "Who Am I This Time?", featuring an actor who entirely inhabits his roles, because he doesn't really have a personality outside of them. Later adapted to an excellent made-for-TV movie starring Christopher Walken and Susan Sarandon, and directed by Creator/JonathanDemme.
* In Creator/RobertAHeinlein's ''Literature/DoubleStar'', the main character is hired to impersonate a kidnapped politician. He becomes so immersed in being this man that [[spoiler:after the original is killed, he takes over and actually becomes him. By the end of the book, he's forgotten he was ever anyone else.]]
* In the Comicbook/XWingSeries, Gara Petothel is a DeepCoverAgent formerly from Imperial Intelligence who no longer has anyone to deprogram her between missions. During one infiltration she's profoundly impacted by the PowerOfTrust and hopes to [[BecomingTheMask Become the Mask]] and embrace the role of Lara Nostil, a [[FarmBoy Farm Girl]]-turned-AcePilot. But then she's contacted by the (dead) Nostil's (fake) brother with a message from the BigBad, complete with doctored family holograms in the background that insert Gara into Lara's life. [[SanitySlippage This is not good for her already fragile mental state]].
** It's implied that going to the EDGE of this, is key to Imperial training. However, being away from her handlers has likely hurt her ability to keep from going over the edge.
** [[spoiler: In the end, it's played with. She purposely becomes lost in the cover identity of 'Kirney Slane'...but only to reclaim something as a 'real her'. She's still aware of Lara, and Gara, but chooses to identify with neither. Lara was a cover identiy, Gara was a bad person. Kirney can be someone new.]]
* In ''[[Literature/DreamPark The Barsoom Project]]'', a young [=LARP=]er named Michelle is handed a working rifle by a saboteur and unwittingly kills an extra in the Fimbulwinter Game. Unable to face what she's done, she convinces herself she really ''is'' her character, "Eviane", who'd shot the man because he was a villain trying to impose EndlessWinter upon the world.
[[/folder]]

[[folder:LiveActionTV]]
* In an episode of ''Series/BuffyTheVampireSlayer'' Drusilla uses her psychic talents to appear to Giles as his former lover Jenny Calendar in order to seduce some information from him. She gets so carried away in the role that she continues making out with him for some time after learning what she was after.
** For that matter, the actors themselves would do this on more than one occasion. Memorably, Creator/SarahMichelleGellar was so invested in her character's romance with Angel that when he turns evil and abuses her, in the scene where she runs home and cries she is so broken up they had to close the set for half an hour.
** When Faith switches bodies with Buffy, she becomes so enamored with Buffy's heroic lifestyle with true friends looking up to her that she tries to actually act the part. She even becomes convinced that Buffy's mind in her old body is actually evil.
* This was parodied in an episode of ''Series/{{Community}}'', when Abed told the story of creating and then ''becoming'' a character for his walk-on role in ''Series/CougarTown''.
** Danny Pudi filmed a cameo on ''Series/CougarTown'' in reference to this scene. It's glorious.
** Abed made up a role for him to play in Cougartown named Chad, and as he made up Chad's backstory in his head, he realized that he had spent all of his life to that point dedicated to pop culture, and Chad had a significantly more fulfilling life than he did. When filming ended and he was forced out of character, he [[HeroicBSOD had a mental crash]], fell over and [[BringMyBrownPants shat himself]].
** Parodied in "Documentary Making: Redux", wherein Jeff is reluctantly cast as the Dean for a short commercial for Greendale and is forced to wear a bald cap over his natural hair. The shoot is only supposed to be for one day, but thanks in part to Jeff's own efforts to try and get out of it it ends up going for almost two weeks -- all of which time Jeff is forced to wear his Dean's costume. Over this time Jeff gradually begins to take on several of the Dean's character traits and becomes convinced that he's actually a bald man who "only dreamed of having hair".
*** This could also be an ActorAllusion--Joel [=McHale=] is actually balding (see [[http://www.complex.com/style/2012/12/the-50-worst-celebrity-hair-styles/joel-mchale this]] photo), and either wears a toupee or has had a hair transplant, depending on who you ask.
* This is arguably the super-power of Echo, the protagonist of ''Series/{{Dollhouse}}''. Despite repeated memory wipes, she always retains the "imprints" of the other personalities she's assumed.
* Possibly Sophie Devereaux in ''Series/{{Leverage}}.'' She mentions before her sabbatical that she's created so many fake personas she's not really sure what's really her anymore and leaves to bury each of them. This extends so far that we're not sure what her real name is.
* This was the plot point in the ''Series/{{Monk}}'' episode "Mr. Monk and the Actor," when a [=TV=] movie was being made about Adrian Monk, starring renowned actor David Ruskin as him. Except, Ruskin has a history of falling too deeply into his roles (for example, once having to spend three months in a rehab clinic after playing an alcoholic in a TV movie, because he managed to have all the symptoms of alcoholism without drinking), and when he portrayed Monk... Afterward, in session with Dr. Kroger, Monk notes that Ruskin has decided to try something less depressing, then adds "[[HypocriticalHumor He's in England playing]] ''Theatre/{{Hamlet}}''."
* An odd example with Jeremy Brett as ''Series/SherlockHolmes;'' he became ill ''while'' obsessing over the character - realizing that he was manic depressive allowed him to start overcoming his obsession to the point where he could enjoy playing Holmes. He died eleven years after ''Series/SherlockHolmes'' first aired, and had quit the series entirely the year before his death.
* In ''Series/TheTwilightZone'' episode "A World of Difference" this is what everybody thinks happened to Gerry Raigan, an alcoholic actor who seems to have snapped and identified too closely with happy executive character Arthur Curtis. He, on the other hand, thinks that he [[SchrodingersButterfly actually is Curtis]], trapped in a nightmare world.
* On ''Series/WKRPInCincinnati'', a well-paying job requires Johnny Fever to play an obnoxious, boisterous host of a televised disco dance show, to the point he actually does begin to lose himself, and becomes frightened this vile character will become him. Twice as interesting for the fact that Johnny Caravella already plays a role as Doctor Johnny Fever - but it is a role he likes. His best friend Gordon Sims tried to lose himself in the role of Venus Flytrap, to escape from the memories of his time in Vietnam. They catch up with him anyway.
* In an episode of the 1970s British TV series ''{{Colditz}}'', an officer in the World War 2 German prisoner of war camp simulates insanity so that he will be repatriated to Britain, the plan being that he will then reveal himself as sane and return to action. His simulation succeeds only too well - at the end of the episode, the prisoners in Colditz receive a letter from the officer's wife relating that he actually went insane and is now confined to a mental institution. The escape committee then decides that no other prisoner in Colditz is to attempt that ploy.
* ''Series/{{Misfits}}'' had a FemmeFatale character who turned out to be this; she was auditioning for a part when the storm happened, and her power made her become that character.
* One episode of ''Series/PressGang'' concerned an actor who played the lead role in children's adventure serial ''[[ShowWithinAShow Colonel X]]'', who had been severely typecast and 'drinking rather too much' before getting into a car crash which killed his wife. Unable to handle it, he started going around in-character as the Colonel, aided by how the press erroneously reported him dead along with his wife. (This is a mashup of problems affecting famous ''Series/DoctorWho'' actors Tom Baker and Rodger Delgado (who played the Master), and the Colonel is played in the show by Michael Jayston, who played the [[EnemyWithout not-quite-Doctor]] the Valeyard. The episode was written by Creator/StevenMoffat, who later went on to... well, yeah.)
[[/folder]]

[[folder:NewspaperComics]]
* This was also parodied in a 2009 ''ComicStrip/{{Garfield}}'' strip, with the dialogue as follows;
-->'''General on TV''': Holy '''bovines''', Corporal! There's a giant monster invading the city!
-->'''Soldier on TV''': That's not a monster, sir.
-->'''General''': What are you talking about? Call out the artillery!
-->'''Soldier''': It's just [[PeopleInRubberSuits a bad actor in a rubber suit]].
-->'''General''': Oh, it is '''not'''! It's a monster!
-->'''Soldier''': Come on... I can see the zipper.
-->'''General''': Egad! A '''zipper''' monster! That's the worst kind!
-->'''Soldier''': And that's not a real city.
-->'''General''': '''Insolence!''' I'll have you '''court-martialed!!'''
-->'''Soldier''': These are just tiny little model buildings.
-->'''Garfield''': General Cordwood seems to have buried himself in the part.
-->'''Soldier''': See?
-->'''General''': PUT MY HOUSE DOWN!!
[[/folder]]

[[folder:ProfessionalWrestling]]
* Back in the days of {{kayfabe}}, it was normal for a wrestler to live his gimmick 24/7.
* During his run as the leader of the Wrestling/MinistryOfDarkness, it was hinted a few times that Wrestling/TheUndertaker was letting his character completely take over who he really was as a person. In a way, this was strengthening {{Kayfabe}} by breaking it.
* According to kayfabe, [[Wrestling/{{Boogeyman}} the Boogeyman]] was an aspiring television actor who couldn't let go of his commitment to a role after his horror series was cancelled.
** There were a lot of rumors floating around about him while he was wrestling; dirt sheets commonly reported that he actually did eat worms back stage(he'd eat them in the ring as part of promos to freak his enemies out...or just because) and that he'd stay in character all the time.
* Wrestling/ElSanto. Lucha Libre legend throughout the 50s and until his death in 1984. He became known for his silver mask, which he only removed once for the public eye, and was buried with it on.
* Wrestling/ReyMysterioJr, too, who in a sense ''is'' his mask. In fact, if you saw him bare-faced, you might not even know who it is.
* The guys behind ''Website/{{WrestleCrap}}'' have suggested this is what happened to Jim Hellwig, [[Wrestling/UltimateWarrior the Ultimate Warrior]], who went so far as to have his name legally changed to "Warrior."
** Born Joanie Laurer, Wrestling/{{Chyna}} did the same thing.

[[/folder]]

[[folder:Theatre]]
* ''Theatre/{{Hamlet}}'' is sometimes interpreted this way, with Hamlet's feigned insanity leading to him actually losing his grip on reality.
[[/folder]]

[[folder:VideoGames]]
* ''VideoGame/MetalGear'' series:
** [[DeconstructorFleet As with so many other tropes]], this one is {{deconstructed|Trope}} in ''VideoGame/MetalGearSolid'': Decoy Octopus is so committed to his disguises that he requires ''deprogramming'' to leave his assumed identities after a mission.
** The purpose of the S3 program imposed upon Raiden in ''VideoGame/MetalGearSolid2SonsOfLiberty'' was to inflict this upon him, turning him from a former child soldier who rewrote his whole past with the power of denial into a second embodiment of Solid Snake.
--->'''Colonel''': This is a type of '[[{{RPG}} role-playing game]]' and I expect you to turn in a perfect performance!
* In one of the many endings on the PC video game adaptation of ''Literature/AndThenThereWereNone'', one of the culprits is an actress who got too far into character and committed a murder for real.
[[/folder]]

[[folder: WebOriginal]]
* In ''Recap/TheFiveishDoctorsReboot'', several of the ex-Doctors are portrayed in this way as part of their copious AdamWesting. Creator/PeterDavison, for instance, is well aware that he isn't actually the Doctor but seems to think that he can actually use the TARDIS to travel in time, and Creator/TomBaker is portrayed [[AlternativeCharacterInterpretation ambiguously]] (via a FakeShemp) - he's either convinced he is the Doctor for real, or he ''actually is'' the Doctor for real.
[[/folder]]

[[folder: WebComic]]
* Taken to frightening extremes in ''WebComic/GuildedAge:'' The five main characters are online gamers selected to take part in a deep-immersion virtual reality role-playing game, and due to the unique magic/technology hybrid nature of the game, they think they actually ''are'' their game characters, with absolutely no memory of who they really are or the lives that they used to have.
[[/folder]]

[[folder:WesternAnimation]]
* In an episode of ''WesternAnimation/KimPossible'' [[AdamWesting The Fearless Ferret]] and White Stripe's actors forget they are actors and think they are their own characters.
-->'''Timothy North''': So what have you been up to lately?
-->'''Rudolph Farnsworth''': Oh living each day in delusion thinking fiction is reality. That's me.
-->'''Timothy North''': Me too.
* In an episode of the "Super Chicken" segment of ''WesternAnimation/GeorgeOfTheJungle'', an actor portraying a Snidely Whiplash-like character abducted the actress portraying the damsel in distress, making her a real DamselInDistress.
* In the second episode of ''WesternAnimation/UltimateSpiderMan'', Agent Coulson is made the new principal at Peter Parker's school, so he can keep an eye on Pete and his friends. Midway through the next episode, he calls Nick Fury, frantically begging for the full power of SHIELD... to help balance the school's budget.
* Happens in ''WesternAnimation/AFlintstonesChristmasCarol'', while Fred is busy rehearsing his part of Scrooge and starts acting like a selfish jerk to his family and friends.
* ''WesternAnimation/TheSimpsons'' has Duffman, whose actor - or at least one of them - openly admits he has no distinct personality our of his costume anymore and cringes to be called by his real name (Larry Duffman).
** It's later implied that this happens to all the actors playing Duffman, when Homer mentions he thought he heard he'd died.
---> '''Duffman''': Duffman can't die, [[TheNthDoctor only the actors who play him]]. Oh yeah!
** One-shot minor Character Senor Ding-Dong was only a man playing the role of a doorbell company mascot, a Zorro-style hero who fixes doorbells with a whip. Then he just became that character entirely.
** Implied to have happened to the ventriloquist operating Gabbo, who repeatedly begs the ''puppet'' to stop calling the audience "SOB's", not realising that the camera was still rolling at the time.
* In ''WesternAnimation/SouthPark'', Cartman creates a very unfunny and very racist handpuppet impersonation of Jennifer Lopez for a diversity event. He soon completely loses control over everything he makes Jennifer do, and "she" gets a record deal despite Cartman's protests, engages in a sexual relationship with Ben Affleck, ends up in hospital thanks to assault from the real Jennifer Lopez, eventually reveals she is actually a con artist named Mitch Connor, swallows a CyanidePill and dies. Subverted in the final hours of the episode when it's revealed Cartman was just doing it to convince Kyle that this trope was in play, so he could laugh at him about it.
[[/folder]]

[[folder:RealLife]]
* This is not unprecedented for practitioners of MethodActing, and can have very real and very negative effects on the actor in question. A good portion of acting training is in fact learning how to avoid this.
* The Canadian actor Raymond Massey, best known for his many, many portrayals of AbrahamLincoln on stage, film, and television, eventually became so obsessed with perfecting his performance that he started to assume the vocal and physical mannerisms of Lincoln in day-to-day life, even appearing at social gatherings dressed in Lincoln-esque clothing. A friend said of his obsession, "Massey won't be satisfied until someone assassinates him."
* Rumours abounded that Creator/HeathLedger's [[Film/TheDarkKnight take]] on SelfDemonstrating/TheJoker was at least in part responsible for his death. The Joker's psyche certainly is unsettling, to say the least. His co-stars seem to debunk this theory as they said he seemed really relaxed between takes and on stage, and in no way exhibited behavior that supports this theory.
* Andy Griffith noted that he had this problem when playing Lonesome Rhodes in ''Film/AFaceInTheCrowd'', and it led him to mostly stay away from such roles for the rest of his career.
* Combined with the substance abuse issues he had at the time, Music/DavidBowie was noted to at least be worried about this happening with some of his stage personas, particularly the unsettling and unpleasant Thin White Duke. This led to him moving away from adopting full characters on stage at around the same time as he pulled himself out of his addiction. To this day, Bowie has stated that he's afraid his Ziggy Stardust character will come back into his mind and drive him completely insane.
** The same thing nearly happened to AliceCooper as his alcoholism spiraled out of control in the 1970s. A stay in a sanitarium pulled him out of it.
* Creator/PeterSellers. Directors often described him as [[FunnyCharacterBoringActor "not having any real personality of his own"]]. At one point during an interview, after demonstrating a wide variety of voices and character types, the interviewer asked if he was now speaking in his real voice. After some hesitation, he replied with a confused "I don't know." When Sellers was the guest on ''TheMuppetShow'', unlike any other guest on the series, he never appeared on-screen out of character. (During the "five minutes to showtime" intro, he's Inspector Clouseau from ''Franchise/ThePinkPanther''.) This appearance is the source of his famous "There is no me. I do not exist." quote.
* Actors who played the Doctor from ''Series/DoctorWho'' have been prone to this, as the Doctor is said to be one of [[BrownNote those]] characters (much like SherlockHolmes) who just gets into an actor's head and erodes their identity, and prolonged exposure is extremely dangerous - most Doctors only play the character for short runs as a protective measure against this. A couple, however, slipped into this:
** Due to the serious mental health problems he was experiencing at the time combined with a punishing shooting schedule, Creator/WilliamHartnell, who played the first [[Series/DoctorWho Doctor]], is reported to have, at times, not known if he was the Doctor or not. He slipped into character to talk his way out of a parking ticket at one point, which is understandable, but apparently would also slip into character to get away from familial obligations, and occasionally even for no obvious reason.
** The other Doctor whose mental health tanked as a result of the role, Creator/TomBaker, would reportedly keep up character whenever he was out and about [[ContractualPurity for the benefit of child fans]], but seven years of being the Doctor both onscreen and off took its toll on both his stress levels and his ability to distinguish ''Doctor Who'' from reality. He was unable to stop comparing himself to the character and experienced intense self-loathing for not being so wonderful and heroic as him, in particular struggling to accept his inability to save people from real problems the way the Doctor could save people from monsters, and founding himself succuming to various personality flaws that he had but the Doctor was [[IncorruptiblePurePureness too perfect for]].
* BobHoskins had a tendency to hallucinate towards invisible animated characters for a short while after filming of WhoFramedRogerRabbit wrapped up.
[[/folder]]

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