->''"I don't remember what my face looks like... or even what my personality was like. My face, memories, personality, beliefs, emotions and soul... I left them all behind. I have no... "self". I am no one. I am nothing but an endless abyss."''
-->--'''The phantom''', ''VisualNovel/PhoenixWrightAceAttorneyDualDestinies''

What happens when your character with VoluntaryShapeshifting begins to suffer SanitySlippage?

You get a ShapeshifterIdentityCrisis, which is the sometimes non-lethal sibling to ShapeshifterSwanSong, and the polar opposite of ShapeshifterModeLock.

Your Shapeshifter character is, for whatever reason, having trouble keeping it together mentally -- so their form switches around in accord with their mental tribulations. The shapeshifter's base identity -- who they are to begin with -- is in danger of getting permanently lost in the mental jumble and resultant physical manifestation of every shape they have ever taken happening at random, on provocation, or if the wind changes.

May be triggered as a result of BecomingTheMask, or may result in BecomingTheMask if you have a ManipulativeBastard guiding the person back from the crisis point. It can also be due to TheMindIsAPlaythingOfTheBody, as having many different forms can make determining which one is the "real you" a bit more difficult.

If the shapeshifter does not survive the crisis, then it's a ShapeshifterSwanSong. If the shapeshifting happens involuntarily due to being sick or some rare condition to the shapeshifter's race, it's MalfunctionMalady instead.

Subtrope to PowerIncontinence.


[[folder:Anime and Manga]]
* The fate of "Copycat" Ken at the end of the ''Manga/RanmaOneHalf'' episode he appears in. His copied forms start to bleed together and he is left begging for help in making it stop. PlayedForLaughs, [[ComedicSociopathy obviously]].
* ''Manga/MajinTanteiNougamiNeuro'' features a really horrific villain whose motivation for his murders is this. He has an out-of-control HealingFactor that allows considerable shapeshifting but also means all of his cells are constantly replicating at horrific speed, [[FridgeLogic ''including his brain cells'']], so he has no idea what his proper form or sex or name or anything are, and his early memories are long since lost.
** He's really pathetic. You feel sorry for him in spite of all the things he's done. Of course, then the ''real'' BigBad turns up and sorts him out...
* In the ''[[Manga/WildFangs Wild Series]]'', all manbeasts lose control of their form when in extended contact with humans, losing their sanity and attacking them. This is traumatic for the manbeasts themselves, who don't harbour any ill-will to humans.
* ''LightNovel/HaiyoreNyarkoSan'' has this in the flash anime ''Remember My Love(craft-sensei)'', with Nyarko's cousin Nyarue. Tends to happen when embarrassed. And considering [[EldritchAbomination them]]... That's a problem. (Though it's censored to protect audience sanity.)
* Chameleonians in ''Anime/SpaceDandy'', who don't even know their true forms, are believed to suffer from this. Even if they don't, they can make their imitatees question which is real one.

[[folder:Comic Books]]
* ''ComicBook/FantasticFour'':
** The entire race of Poppupians are an inversion to this trope. They exist naturally in a state where they have no solid identity and switch fluidly and easily from shape to shape. Their natural state is to identify more or less as ''each other'', so they don't really have a base identity to lose or worry about getting back.
* Delirium, the personification of madness in ''Comicbook/TheSandman'', sometimes transforms involuntarily into multicoloured butterflies or fish.
* Chameleon (of the ''Franchise/SpiderMan'' rogues gallery) has ended up like this at least once. He realized that he didn't have an independent identity anymore - just a big collection of faces stolen from his enemies. So he ends up in an asylum, switching continuously from one identity to the next, desperately searching for a face to call his own...
* Captain Britain's lover Meggan in ''Comicbook/{{Excalibur}}'' had this in personal relations at times; her limited shapeshifting became more responsive to her empathy the closer she became to someone. Even the form she most often took (beautiful, blue-eyed, [[MostCommonSuperpower busty]] blonde) was a response to falling for Brian Braddock at first sight. But she also would shift to look more like Colossus or Nightcrawler if she was bonding with them.
* In ''Comicbook/MsMarvel2014,'' this happens to Kamala when she first gets her powers; left in a state of confusion, she transformed into her hero, Carol Danvers, and thus wound up [[LegacyCharacter taking Carol's old "Ms. Marvel" title]].
* In ''ComicBook/AdventureTimeMarcelineAndTheScreamQueens'', one shapeshifting character has changed forms so many times he not only can't remember what he originally looked like, he can't remember his real name. He tries to pass himself off as [[OurWerebeastsAreDifferent a variety of different were-creatures]], with his "true" form being [[spoiler:a nondescript human man with the name Guy - as in, "guy who can shapeshift"]].

[[folder:Fan Fiction]]
* One ''ComicBook/YoungAvengers'' fanfic involves this. After being ambushed while on holiday, Wiccan comes home to reveal that he can no longer use his magic and that Hulking "is gone", with the obvious implication being that he's dead - the fic's ArcWords being "Teddy's gone." It takes a year for Tommy to realise the truth and confront Billy with it - that [[spoiler: Billy was the one who died in the attack, and Teddy has been using his shape-shifting abilities to live Billy's life in his stead (his reasoning being that the world in general had a lot more to lose from Billy's death).]] By the end of the fic, and throughout the follow-up, [[spoiler: Teddy seems to genuinely believe that he's Billy, and that it's himself who died - his grief prevents him from accepting the truth, and he ends up BecomingTheMask.]]

* Mister Nobody, from the ''WildCard'' series, was trapped in the form of Film/KingKong for nearly thirty years before someone realized that, since apes are immune to the wild card virus, the Giant Ape had to be an actual ''person'' inside that form. He was rescued by the telepathic Doctor Tachyon, and has since got his life together for the most part.
* In ''Literature/{{Animorphs}}'' #35, Marco can't deal with the stress of his [[ParentWithNewParamour father marrying his math teacher]] (because he doesn't realize that [[DeathFakedForYou Marco's mom isn't really dead]]), so he starts to morph {{Mix and Match|Critters}}. A similar plot occurs with Rachel in #12 (with InvoluntaryShapeshifting), although this is due to an allergic reaction.
* An early example happens in Creator/HarlanEllison's short story, "All the Sounds of Fear", in which Stanislaviskian actor Richard Becker, famous for becoming his roles and avoiding the limelight personally, goes insane and starts to become each of his roles again, going backward. At one point, when he switches from one role to another, we're told that his face seems to almost physically shift. And at the end after he's been his first role again, [[spoiler:we get our last glimpse of him in a cell at the asylum, screaming "Give me some light!" over and over again, his face an eyeless blank.]]
* {{Inverted}} in ''Literature/HarryPotter''--[[HumanShifting Tonks]] was unable to shapeshift through most of book 6, because of her extreme stress that [[spoiler:she's in love with Lupin]].
* In ''Literature/GalaxyOfFear'' Hoole is against using a permanent fake identity.
--> "To a Shi'ido like me, identity is everything. I must always remember who I am. Otherwise, with all the shape-changing I do, I am in danger of forgetting who I really am."

[[folder:Live-Action TV]]
* A VillainousBreakdown version happens with Sylar from ''Series/{{Heroes}}''. The already mentally unstable serial killer with ParentalIssues gains shapeshifting and begins cycling back and forth between his mother's form and his own as he has a conversation with himself via what he thinks she'd say. This eventually leads him to write 'I AM SYLAR' in blood at his next murder scene as he desperately tries to hang onto who he wants to be.*
* An interesting version occurs in an episode of ''Series/TheFlash2014''. After spending the entire episode impersonating various people before finally being caught, Hannibal Bates is finally apprehended and imprisoned. Wells notes that they've seen Bates become a lot of people...but never ''himself'' and asks him who ''he'' is. Bates' response? "I...can't remember.".
** In supplemental materials, Cisco attempts to help Bates remember and he responds negatively to it. He apparently doesn't want to remember.

* The ''Music/FlandersAndSwann'' song "The Chameleon", ends:
-->''"If that chameleon were me, I'd be ashamed to sham.\\
Each night, all white, between the sheets\\
I'd wonder who I am."''\\

* In ''Aberrant'', Turncoat was initially an agent of the Directive, an organization that distrusts most novas and recruits only those with low-key powers, or those that can be used for subtlety. After infiltrating the nova-supremacist Teragen, he slipped rapidly into their belief system despite his initial intentions. As part of the story of "When Heaven Ends", the last of the canonical adventures, he accidentally transforms into someone who is covertly scanning him, believes himself to be that person, and runs off just in time to escape the colossal battle his actions helped set off.

[[folder:Video Games]]
* The BigBad of ''VisualNovel/PhoenixWrightAceAttorneyDualDestinies'' is [[spoiler:"the phantom", a spy who is so adept at impersonating others that his original identity has long been lost even to himself. As such, when blood evidence is finally discovered tying him to his multiple crimes, he starts to break down ''because he has no idea who the "him" that would be caught is!'' This results in him [[VillainousBreakdown tearing off mask after mask, desperately trying to find his true face]]. Just as he tears off his last mask, he's shot by a sniper, and his body falls in such a way that his face (and only his face) [[TheUnreveal is obscured by darkness]].]]

[[folder:Web Original]]
* The Blank, from the ''Roleplay/GlobalGuardiansPBEMUniverse'', is a shapeshifting teenager who can make himself... or possibly herself... look like any human. She... or perhaps he... has lost track of his... or is it her... original gender and appearance. The fact that her... or is it his... real name is "Leslie" (one of the few details of his... or is it her... original life that she... or is it he... remembers) doesn't help matters.
* [[http://brawlinthefamily.keenspot.com/2013/01/29/459-kirby-transforms/ This comic]] from ''Webcomic/BrawlInTheFamily'' has Kirby copying other characters who can copy other characters, eventually turning into Deku Link while saying, "I don't know who I am anymore...."

[[folder:Western Animation]]
* ''WesternAnimation/XMenEvolution'' Rogue already has mental instability problems due to her mutant copycat power generating copies of the minds and personalities of those she touches. After touching Mystique and acquiring her shapeshifting (and discovering the latter is a MagnificentBastard manipulator) shapeshifts into various heroes and villains she's touched, in response to things said to her or people she encounters.
** In the [[WesternAnimation/XMen original cartoon]], when Morph first [[BackFromTheDead returns from the dead]], he's in bad [[SplitPersonality mental]] [[BrainwashedAndCrazy shape]], and thinking of his "former" friends tends to result in him unconsciously taking their forms.
* ''WesternAnimation/IronManArmoredAdventures'': Whitney Stane's Madame Mask mask becomes the vehicle for the same sort of shapeshifting switcheroo when the technology powering it gives her brain damage, resulting in SanitySlippage.
* In ''WesternAnimation/MightyOrbots'', Bort suffers from this due to his lack of self-confidence and ongoing identity crisis.
* In ''WesternAnimation/BatmanTheAnimatedSeries'', Matt Hagen was already in crisis before [[CorruptCorporateExecutive Roland Daggett’s]] goons poured MutagenicGoo on him and turned him into Clayface. Once transformed, the former actor believes his life is over until he starts to reminisce on his past movies and begins [[InvoluntaryShapeshifter involuntarily shapeshift]] into his past roles. Naturally he decides to use his newfound power to seek [[RoaringRampageOfRevenge revenge]] on Daggett but in the process he starts to become more unstable and aggressive, even violently lashing out at his best friend. In the end, Batman knocks Clayface into a room of televisions featuring pictures of his past selves. [[VillainousBreakdown His shape shifting goes]] [[https://www.youtube.com/watch?v=76-8xyGf7w0 berserk.]]