So your story was a smash success, and you've gotten enough interest or capital to do a sequel. However, you fear that you fully explored all of the characters in the first story and of course it would stale your writing ability to [[SequelReset retread the same characters and events from the first story]]. So you need a way to not only stretch your storytelling chops, but also hand out enough {{Shocking Swerve}}s to keep the audience surprised. How do you do this?

Why, by turning one of the main [[FaceHeelTurn good guys into a bad guy!]]

[[TropesAreNotBad When done correctly]], a FaceHeelTurn can be shocking, compelling and tragic. Few things tug at the heartstrings like when [[BreakTheCutie a cutie is broken]] or when TheParagon crosses the DespairEventHorizon and [[GoMadFromTheRevelation goes bonkers over the unfairness of it all]]. [[TropesAreNotGood When done poorly]], the turn comes out of [[ShockingSwerve absolutely nowhere]] or [[CharacterDerailment betrays the expectations that had been set by the character's portrayal up til then]]. Audiences tend to become attached to their heroes and some become more "icons" than characters, leading to the audience feeling betrayed by not only that character, but the writers themselves.

If this is a prequel, and an enemy from the original is part of the group, then this is DoomedByCanon to happen.

A subtrope of FaceHeelTurn. Separate from (but not mutually exclusive to) SuddenSequelDeathSyndrome.

SuperTrope of RogueProtagonist, FallenHero, and TheParagonAlwaysRebels. See also RonTheDeathEater for fanfiction, and AdaptationalVillainy.

'''WARNING: May contain spoilers.'''



[[folder: Anime/Manga ]]

* Joker, the head of the British Library special forces in ''Anime/ReadOrDie''. Between the OVA, where he's on the side of the good guys, and R.O.D The TV, the death of Gentleman (the ManBehindTheMan of hundreds of years of British history who envisioned a sort of Utopia under the British Empire) shifts Joker into WellIntentionedExtremist territory, working toward what he sees as Gentleman's dream by means ranging from ethically dubious to outright evil.
* ''Anime/YuGiOh'' Season 4 turned Mai Valentine, the gang's CoolBigSis, into an angst-ridden member of a villainous biker gang. It turns out she was tricked into HeelFaceBrainwashing by the arc's BigBad, Dartz.
* In the sequel to ''Manga/BoboboboBobobo'', Gasser switches sides and becomes a hair hunter to protect his [[RememberTheNewGuy previously]] unmentioned sister from harm.
* In the third season of ''Anime/CardfightVanguard'', Kai (the resident InvincibleHero) is on the receiving end of a HannibalLecture and ends up BrainwashedAndCrazy, becoming the emissary for the main bad guys.
* Season 3 of ''LightNovel/ShakuganNoShana'' [[spoiler: has the male protagonist, Yuji Sakai, of the first two seasons, suddenly becoming the BigBad, leaving the female lead and love interest Shana shocked and confused.]]
* Played straight and zigzagged in ''Manga/TokyoGhoul''[=:Re=], which takes place after a two year TimeSkip:
** [[TheCutie Hinami]] Fueguchi was [[CorruptTheCutie enticed]] to join [[TheSyndicate Aogiri Tree]], through her desire to become stronger. She returns as a prominent member handling the group's intelligence network.
** PluckyComicRelief Seidou Takizawa turns out to be NotQuiteDead, and returns as an AxCrazy [[HalfHumanHybrid One-Eyed Ghoul]] serving as Aogiri's first successful SuperSoldier. He proceeds to slaughter his way through every Investigator he crosses paths with, taking the time to chat with a former pupil before tearing her head off because she used to talk during lectures.
** Played with, depending on [[GreyAndGrayMorality which side]] has the SympatheticPOV. Ken Kaneki returns as AmnesiacHero Haise Sasaki, working for the [[TheHunter CCG]] as a Ghoul Investigator and mentor to an experimental squad of SuperSoldiers. While he remains the protagonist, his former friends now have to worry about him hunting them down if they cross paths again.


[[folder: Comics ]]

* Comics in general loves a FaceHeelTurn, but usually don't qualify for the trope unless the character gets PutOnABus for a while and returns evil. A few notable examples include:
** Jean Loring in ''ComicBook/IdentityCrisis'', who went completely off her rocker to try winning back the affection of her ex-husband, [[ComicBook/TheAtom Ray Palmer]].
** The survivors of ''ComicBook/CrisisOnInfiniteEarths'' (Superboy-Prime, Superman (Kal-L), and Alexander Luthor) all became contemptuous of the ModernAge DCUniverse and launched a scheme that would forcefully return things to UsefulNotes/{{the Silver Age|of Comic Books}} status quo, whether the universe was ready or not, on ''ComicBook/InfiniteCrisis''.
*** Though it should be noted that [[spoiler:Kal-L was just an UnwittingPawn, he turned back to Face the second he realized what was really going on, and ultimately [[HeroicSacrifice gives his life bringing down Prime]]]].
** [[ComicBook/{{Supergirl}} Linda Danvers]] retired from superheroics after ''Many Happy Returns'', but returned in ''ComicBook/{{Shadowpact}}'', transformed into a vengeful "Fallen Angel".
** [[ComicBook/{{Batgirl 2000}} Cassandra Cain]] during DC's ''OneYearLater'' storyarc. This was not a popular storyline (she was quite OutOfCharacter even ''aside'' from the evil) and eventually got {{Ret Con}}ned into mind control.
** Max Lord had always been depicted as a somewhat egotistical businessman who recreated the Justice League in part to make himself look good but ultimately proved to be a fairly honorable person. Then came ''ComicBook/InfiniteCrisis'', in which he turns out he founded the new League in order to undermine all superheroes. And even worse, it reveals that he was ''always'' evil, despite readers having seen his inner thoughts at multiple points in that Justice League run to prove otherwise.
** In [[ComicBook/TheUltimates The Ultimates 2]], Black Widow is revealed to be [[TheMole a mole]] working for the Liberators and her native country, Russia.


[[folder: Fan Fiction ]]

* Inverted in ''Fanfic/ThePrayerWarriors'', [[Literature/PercyJacksonAndTheOlympians Clarisse, Annabeth and Grover]] were villains in ''The Evil Gods Part 1'', but they inexplicably get brought back as being on the Prayer Warriors' side (in addition to being brought BackFromTheDead, but [[DeathIsCheap that's another issue]]). Then again, this might be a straight example when you consider that the Prayer Warriors murder anyone who disagrees with them.
* In ''Fanfic/HalfLifeFullLifeConsequences'', Gordon Freeman, TheHero from canon and the protagonist's heroic brother in this fanfic, comes BackFromTheDead in "What Has to Be Done", as a "zombie goast" who wants to kill his brother out of revenge, [[spoiler:and again as a BrainwashedAndCrazy slave of the Combines in "Free Man", although once he's defeated, he [[DyingAsYourself dies as himself]].]]


[[folder: Film ]]

* In the original ''Film/RoboCop1987'', the CEO of Omni Consumer Products is merely an amoral old man who really doesn't do anything outright villainous, but shows little empathy for others. In [[Film/RoboCop2 the sequel]], he's a flat-out CorruptCorporateExecutive.
* ''Film/TronLegacy'' does this to [[spoiler:Tron himself aka Rinzler, courtesy of being corrupted by [[BigBad Clu]]. He has a HeelFaceTurn and a HeroicSacrifice near the end of the film, though.]]
* ''Film/{{Star Trek VI|The Undiscovered Country}}'' turns Admiral Cartwight from ''Film/{{Star Trek IV|The Voyage Home}}'' into a co-conspirator with the bad guys.
** And the film was going to have Saavik as another conspirator, until Gene Roddenberry personally stepped in and forced them to change her to a new character, Valeris; he recognized that turning a beloved character into a murderous traitor wouldn't sit well with fans. Imagining her as Saavik makes Spock's stunned reaction to her betrayal make a bit more sense.
* The first ''Film/MissionImpossible'' film turns Jim Phelps, the unwavering mastermind of the original series, into a bitter cynic who betrays his team for a multi-million dollar payoff. To say that fans of [[Series/MissionImpossible the original series]] were angry would be an understatement. Greg Morris, who played Barney Collier in the original, walked out of the movie in disgust, while Peter Graves and Martin Landau also voiced their displeasure (Graves turned down an offer to reprise his role as Phelps because of this).
* Ugg the alien bounty hunter who was one of the heroes in the first three ''Film/{{Critters}}'' film is the main villain in the fourth film.
* Inverted in ''Film/Terminator2JudgmentDay''. The robot played by Arnold Schwarzenegger was the antagonist in the first film. In the sequel Arnold is the one protecting John Connor this time, while the robot played by Robert Patrick is the villain. At the time this was the big twist, but [[ItWasHisSled it's now widely known]].
* ''Film/CaptainAmericaTheWinterSoldier'' reveals that the titular Winter Soldier is [[spoiler: Cap's old war buddy Bucky Barnes]] now BrainwashedAndCrazy. Uniquely for this trope [[spoiler: he's redeemed at the end]].


[[folder: Literature ]]

* In the first story of G.K. Chesterton's ''Literature/FatherBrown'' series, detective Aristide Valentin of the Paris police force is a likable InspectorLestrade to the title character, totally fooled by Father Brown's ObfuscatingStupidity but competent enough to follow the trail of clues the little priest leaves for him. In the next story, [[CharacterDerailment however]], he becomes a StrawAtheist who murders a man to prevent him from leaving money to the church in his will. (And, for extra irony points, the villain from the first story is subsequently given a HeelFaithTurn to become TheWatson.)
* In ''Literature/InheritanceCycle,'' [[EnsembleDarkhorse Murtagh]] turns evil in the second book, because [[BigBad Galbatorix]] [[IKnowYourTrueName knows his true name]].
* In ''Literature/DoraWilkSeries'', after being Dora's staunch ally for first five books, Katarzyna turns against her in the sixth one, suddenly having issues with Dora's mixed blood - a fact known even before the series started. She mostly has problems with the fact that by the series finale, Dora doesn't even try to hide her mixed heritage, which Katarzyna finds disgusting.
* Atticus Finch, an iconic hero in ''Literature/ToKillAMockingbird'' becomes a senile old racist in its sequel, ''Literature/GoSetAWatchman'' (written first but published and set afterwards). This is shocking both in and out of universe, with Atticus's daughter expressing her distaste, and many critics have also voiced displeasure at the dismantling of one of the most inspiring heroes in American history.
* ''Literature/HarryPotterAndTheOrderOfThePhoenix'' has Harry returning to the Weasley family only to find out that Percy has fallen out with everyone and sided with the Ministry of Magic ahead of the upcoming war.


[[folder: Live-Action TV ]]

* Sikozu in ''Series/{{Farscape}}: The Peacekeeper Wars.''
* In ''Film/KamenRiderXSuperSentaiSuperheroTaisen'', former [[Series/KaizokuSentaiGokaiger Gokai Red]] Marvelous actually takes command of a LegionOfDoom to further his quest for the Greatest Treasure. [[spoiler: All a plan between the Super Sentai and the Kamen Riders to manipulate the bad guys, of course]].
** ''All'' the Gokaigers in the usual teamup with Go-Busters. Naturally, they were also faking it.
* During the original run of ''Series/DoctorWho'', Chancellor Borusa had in the past been depicted as a politically motivated member of the Time Lords High Council, but ultimately someone whom the Doctor could work with and even regard as a friend. In "The Five Doctors", he turned out to be the villain, orchestrating a mad scheme to resurrect Rassilon and gain immortality.
** Admittedly, every time the show returned to Gallifrey, it seemed that more of the cracks in the Time Lords' "perfect society" would show, to the point where the Doctor would call them out, declaring them, "the oldest civilization, decadent, degenerate and rotten to the core!" By the time of the new series, the entire Time Lords species had crossed a collective MoralEventHorizon, plotting to destroy all of time to preserve themselves. This ended up being retconned, however, as the actions of a small minority of Time Lords, after which they save the Doctor's life by granting him a new regeneration cycle.
* In an episode of ''Series/BurnNotice'', TheWoobie hires Michael to rescue his kidnapped daughter. In the next episode, the same man is the villain, as his RoaringRampageOfRevenge against the men responsible claims innocent lives and Michael takes it upon himself to stop him.
* ''{{Series/Charmed}}'':
** Cole Turner began as a straight up AntiVillain before undergoing a HeelFaceTurn. He was possessed by an evil entity in Season 4 and [[spoiler: forced to be killed]]. When he returns in Season 5 he's presented as a straight-up villain.
** The Crone was a TrueNeutral in her first Season 5 appearance - calling a truce between good and evil to prevent bloodshed over Wyatt Halliwell. Her second appearance has her as a villain who tries to kidnap the child herself.


[[folder: Professional Wrestling ]]

* This often happens to some wrestlers who are lower down on the card, especially in developmental. While creative works out the kinks in their character, they may just randomly appear in a different role on a new episode. For example they might be a face in their first few appearances and then inexplicably switch to heel.


[[folder: Radio ]]

* Nicholas Adamsworth (voiced by Dick Beals), a minor character from ''AdventuresInOdyssey'', was an ethical, well-meaning child-prodigy in his first two appearances. He came back many episodes later as a hacker who changed people's grades to bribe some students and to get revenge on others. His change in character is lampshaded, but the reasons for it are never actually explored beyond a nonchalant handwave on how some people change for the worse over time.


[[folder: Videogames ]]

* [[{{UsefulNotes/Masamune}} The Masamune sword]] in ''VideoGame/ChronoCross''. In the ''VideoGame/ChronoTrigger'', the Masamune is a coveted magical weapon which is said to be the only the only weapon capable of hurting the wicked sorceror, Magus. It's outright said many times that only the [[TheChosenOne Legendary Hero]] can wield the sword and at one point, said Hero even goes through a SecretTestOfCharacter which allows the sword to recognize him as its true owner and unlock its full potential. Then, in the sequel, the Masamune is explicitly stated to be an "evil" sword and anyone who wields it will immediately go insane. However, this is {{Hand Wave}}d in that the Masamune is sentient and inhabited by two mischievous young spirits. When their big sister shows up and smacks some sense into them, the Masamune becomes good again.
* Gray Fox, Schneider and Dr. Pettrovich were originally on Solid Snake's side in the first ''VideoGame/MetalGear''. In ''VideoGame/MetalGear2SolidSnake'', all three defected to Zanzibarland for personal reasons.
** ''VideoGame/MetalGearSolid2SonsOfLiberty'' cheerfully subverts this - the villain claims to be Solid Snake, but he clearly isn't.
** Sigint, Para-Medic and Zero in ''VideoGame/MetalGearSolid4''. It can be argued that their creation in the first place was to explain the StartOfDarkness which lead to the creation of "The Patriots", but few can argue that it's a shock to learn that the [[MorallyAmbiguousDoctorate amoral "Dr. Clark"]] we heard about in the first game was the sweet and flighty Para-Medic (it doesn't help matters that the first game retroactively misgendered Dr. Clark as a male).
* In the 2009 VideoGame/BionicCommando game the BigBad is revealed to be [[spoiler:Super Joe, the war hero you rescued in the original Bionic Commando.]]
* ''FinalFantasyX2'' inverts it. Tromell Guado was TheDragon to Seymour, actively sending people out to kill the protagonists after discovering they murdered Seymour. In the two year TimeSkip the entire Guado race suffered a collective MyGodWhatHaveIDone - and were exiled to the Macalania Woods. One sidequest is preventing the Ronso from slaughtering the tribe. If the player does things correctly [[spoiler: Tromell will become the new leader of the Guado and direct them towards a brighter future]].
* ''[[VideoGame/{{Diablo}} Diablo II]]'': the protagonist of the original is now the Big Bad.
** Justified in that at the end of the first game the protagonist [[spoiler: was forced to take Diablo's soul into his own body in order to contain him. The simple explanation was that it didn't work.]]
** The other heroes, the Mage and the Rogue, also become bosses. It ''is'' a CrapsackWorld after all.
* Lloyd Irving in ''TalesOfSymphoniaDawnOfTheNewWorld''. Well, sort of. [[spoiler: It was an impostor and the real Lloyd was only hindering your goals because he was trying to set things right as well.]]
* In the ''VideoGame/WingCommander'' video game series, the game Wing Commander III: Heart of the Tiger had [[spoiler:Col. Ralgha nar "Hobbes" Hhallas who was throughout game 2 a ProudWarriorRaceGuy who was disgusted with his race's lack of honor suddenly do a FaceHeelTurn in which he turns out to have been a sleeper agent hiding behind a fabricated personality]].
** Likewise, the BigBad of Wing Commander IV: The Price of Freedom [[spoiler: turns out to be Admiral Tolwyn, who lost his direction in life and ultimately went rather nuts once he no longer had a war to fight. Although he was something of a jerk towards your maverick ace character throughout the series, he was also mostly the main BigGood.]]
* This happens to heroine turned ActionMom, Sophitia Alexandra, in ''VideoGame/SoulCalibur IV''; where she's made to defend VideoGame/SoulEdge in order to save her daughter's life.
** It also happens to the eponymous Soul Calibur itself in the fourth game; when the sword reaches full power and gains sentience, it's revealed that the Calibur, long thought to be the "good" sword throughout the series, is technically just as "evil" as the Soul Edge. The difference is that the Soul Edge likes to spread chaos and misery while the Soul Calibur [[WorldOfSilence wants tranquility, order and peace... by freezing the entire world solid]].
* Vladimir Lem in ''VideoGame/MaxPayne2TheFallOfMaxPayne''. It wasn't that he was a particularly nice guy to begin with, being a high-ranking member of the local Russian mob as well as [[MadBomber more fond of explosives than is strictly healthy]], but he was a WorthyOpponent in an EnemyMine situation. As Max himself puts it:
--> ''"Vladimir was one of those old-time bad guys with honor and morals, which made him almost one of the good guys. None of us was a saint."''
* ''{{VideoGame/Contra}}: Shattered Soldier'' reveals that the Blood Falcon Commander is none other than Lance Bean, Bill Rizer's partner from earlier games. [[WellIntentionedExtremist He went insane]] trying to reveal the GovernmentConspiracy he and Bill were duped into helping cover up. Likewise, in ''Neo Contra'', [[spoiler: Lucia, player 2 in ''Shattered Soldier'']] is revealed to be part of the QuirkyMiniBossSquad and dies attempting to kill Bill and exterminate humanity for reasons which are not even vaguely explained.
* Alex Mercer becomes the BigBad in ''VideoGame/{{Prototype 2}}'' after crossing the DespairEventHorizon. The fandom has been [[BrokenBase split]] over this.
* ''VideoGame/WorldOfWarcraft'' has gone ''hard'' on various characters from the [[VideoGame/{{Warcraft}} previous games]] or the [[Franchise/WarcraftExpandedUniverse expanded universe]] in order to turn them into bosses which may be killed for loot.
** Illidan is a notorious example, to the point where Blizzard has vowed to one day bring him back and redeem him to make up for it. They even admitted that they only made him a villain so the expansion would have a popular character to confront and get loot from.
*** In ''Warcraft III'' Illidan was a complex AntiHero who used any means necessary to save his people, but despite fears from those around him, never succumbed to the corruption of the dark powers he was toying with. This finally came to light when his brother attempted to stop him from destroying Northrend, only to find out after disrupting the spell that Illidan was only trying to destroy the Frozen Throne and the Lich King. After saving their mutual love, Illidan saw the error of his ways and they parted on good terms. In ''Burning Crusade'', with the [[HandWave flimsy explanation]] that he went crazy after losing to Arthas, Illidan is suddenly a CardCarryingVillain who is even known to sabotage his own goals if it means he [[ForTheEvulz gets to do something evil]]. This culminates in his death, where you are assisted by a character who is arguably an inversion of this trope. Maiev had dogged Illidan before as an insanely zealous InspectorJavert who went [[MoralEventHorizon too far]] into KnightTemplar territory, but is treated like a mostly heroic paragon of justice here.
** Sylvanas wasn't exactly the most shining example of heroism, but her character in ''Frozen Throne'' revolved around how horrible a fate undeath was. Arthas raised her as a banshee while defending her homeland just so he could force her to massacre the very people she died defending. Even when she regained her mind and body, she still saw undeath as a fate worse than death that no one deserved, and wanted nothing more than to get revenge on Arthas and stop the Scourge once and for all before finally dying and being able to rest. Come ''World of Warcraft'', Sylvanas is creating plagues that are explicitly worse than the ones the Scourge employed, and she suddenly likes talking about how she wants to kill the living and proliferate her undead "race". After Arthas is finally killed, she becomes the exact thing she hated in Arthas: using the Val'kyr to raise Lordaeron farmers and Galen Trollbane specifically to fight and kill their own families, with not the briefest hint of irony or justification for the blatant hypocrisy. She makes the Forsaken nation into a fascist dictatorship with a cult of personality and a heavy dose of hypocritical nationalism as justification. In her short story, ''Edge of Night'', she also claimed that she doesn't actually care to die for her people at all, and only sees the Forsaken as fodder to keep herself from dying and meeting the hell that awaits her in the afterlife.
** Kael'thas is another example. In ''Frozen Throne'' the blood elves were the epitome of the concept that [[DarkIsNotEvil a scary name does not mean evil]]. Kael'thas was arguably one of the most heroic characters in the campaign. He fought for a place for his people after the destruction of their homeland, he assisted the night elves, who his people were exiled from long ago, his actions even saving their leader, Tyrande, and he contributed as the sane man and moral center to Illidan's morally ambiguous outcasts. In ''Burning Crusade'', he's eventually revealed to be TheMole in Illidan's army for the Burning Legion, and is even implied to be the true reason for many of Illidan's most evil tactical decisions, in a way that couldn't be further from his original characterization. Blizzard expressed regret at this change as well, but after almost immediately bringing him back from the dead as an even more desperate Legion pawn, figured they missed their chance to properly repair his character.
** Garrosh Hellscream is an oft-argued version of this trope. He goes from an ineffectual but lore-important side character in ''The Burning Crusade'', to a warmongering {{jerkass}} with a following in ''Wrath of the Lich King''. He appears to gain some character development in ''Cataclysm'' by executing an officer who killed children and showing that he [[EvenEvilHasStandards has standards]] when interacting with Sylvanas, but he goes full-villain in ''Mists of Pandaria'' and becomes a genocidal warlord who wants to subjugate the entire world, sees orcs as the MasterRace, uses {{Fantastic Nuke}}s at the drop of a hat, attacks his own allies the second they refuse to obey, and doesn't care about working for an [[EldritchAbomination Old God]] if it leads to victory.
** The orcish race and the Horde as a whole have been struggling with this trope in a more general sense. One of the major plot points of ''Warcraft III'' was that the orcs weren't AlwaysChaoticEvil, and Thrall was building a new Horde that was good. By the end of the game, he's succeeded, and the Horde, Alliance, and night elves save the world and celebrate together. Right off the bat in ''World of Warcraft'' however, you have the Horde getting the darker races like the Forsaken, who are openly doing horrible experiments on innocent civilians. In ''Wrath of the Lich King'', the Horde players help to create the new plague that is used to devastate both Horde and Alliance forces at the Wrath Gate, and while its use was the result of a coup, Sylvanas openly works on such projects and talks about killing all life. In ''Cataclysm'', while the exact start of the war is a bit ambiguous in canon, the Horde are the main aggressors, gleefully defiling sacred lands, massacring civilians, and generally keeping the Alliance on the defensive. This war culminates with Garrosh essentially dropping an atomic bomb on a city that once championed for peace. While the majority of the Horde ultimately rebels in ''Mists of Pandaria'', most of the damage had already been done by that point, and most of the rebelling happens as a result of Garrosh personally attacking or insulting his allies, not them being horrified by his atrocities and war crimes. While ''Warlords of Draenor'' ostensibly recovers from this, with Garrosh no longer leading the Horde, we get the unfortunate implication from the Iron Horde that the orcish race (and the Horde) are genocidal conquerors by default. Even the Frostwolf [=NPCs=] (the only good clan) threaten to kill Alliance characters (who their only experience with in this timeline is positive) for no apparent reason, and main timeline Horde questgivers are shown acting and talking like they're still under Garrosh.
** The Zandalari trolls were introduced as allies of Horde an Alliance alike, seeking to stop the return of Hakkar and record the history of the collapsing Drakkari troll empire. In ''Cataclysm'' they began inciting the Amani and Gurubashi to reclaim their empires due to growing fears about trolls being wiped out. ''Mists of Pandaria'' escalated this when the Zandalari willingly joined forces with [[LawfulEvil the Thunder King]]. Here their reason is finally explained: [[DrivenToVillainy The Cataclysm is causing their homeland to sink into the ocean; without a new homeland they'll be wiped out]].
* The AxCrazy BigBad of ''ArmyOfTwo 3: The Devil's Cartel'' is revealed to be [[spoiler: Salem, one of the two main characters from the first two games.]]
* In ''VideoGame/FireEmblemAkaneia'', Hardin is on the hero's side in Shadow Dragon. In Mystery of the Emblem's second book, it is revealed that he has turned evil.
* [[spoiler:Penelope Mouse]] from ''Franchise/SlyCooper'' turns bum at some point between [[VideoGame/Sly3HonorAmongThieves the third]] and [[VideoGame/SlyCooperThievesInTime fourth]] game, [[AssPull and it came right the hell out of nowhere]].
* ''[[VideoGame/DonkeyKong Donkey Kong Jr.]]'', the only professional game in existence to treat {{Mario}} as the main antagonist.
* Leon Silverburg in the ''VideoGame/{{Suikoden}}'' series went from a [[VideoGame/SuikodenI recruitable ally]] to a WellIntentionedExtremist in [[VideoGame/SuikodenII the sequel]]. This is a justified example, though - the stories are always set in different countries (and different points in time, though ''II'' is only several years after ''I''), and so the characters who do reappear will take different approaches based on who they're working for. Leon isn't even a villain anyway, he's just taking a different approach (''Suikoden'' thrives on GreyAndGrayMorality), so he's not really that different from the original game in terms of personality.
* ''Videogame/{{Dead Rising 3}}'' brings back [[spoiler:Isabella Keyes]] as the BiggerBad and WellIntentionedExtremist behind all of the events of that game. In a lesser example, [[spoiler:Chuck Greene]] becomes a crime boss [[spoiler:to provide his daughter Katey with more Zombrex. This drove away his LoveInterest Stacey from the previous game and Katey, who took on a different name "Annie" and ran away from home.]]
** Also, in the AlternateContinuity of ''Dead Rising 2: Off the Record'', [[spoiler: Chuck Greene]] goes crazy and becomes a psycopath after [[spoiler: Katey]] dies.
* In Season Two of ''Videogame/TheWalkingDead'', it is shown that [[spoiler:the group that the protagonists of the 400 Days DLC can possibly join is none other than Bill Carver's group. However, Bonnie ends up helping Clementine and her group escape Carver and ends up going with them by the end.]]
* In ''VisualNovel/SuperDanganRonpa2'' [[spoiler:BigBad Junko Enoshima attempts to convince the survivors that Makoto Naegi, TheHero of the first game has fallen victim to this.]] He hasn't.
* Though calling [[WildCard Ada Wong]] a "good" guy is being rather generous, she was never as outright heinously evil as she is in ''VideoGame/ResidentEvil6'' where she mercilessly infects the same soldiers who protected and escorted her to safety [[ForTheEvulz just for kicks]] and is soon discovered to be the leader of a [[NebulousEvilOrganization NEO Umbrella]] that plans to [[TheEndOfTheWorldAsWeKnowIt destroy the world]]. [[spoiler:It's revealed that Ada is actually [[EvilTwin a woman named Carla Radames]] and the ''real'' Ada is still the same [[DeadpanSnarker snarking]] [[DatingCatwoman Leon-loving]] AntiVillain she always was and is actively working to stop Carla.]]
* ''VideoGame/KnightsOfTheOldRepublic'':
** In the first ''Knights of the Old Republic'', Master Vrook is a character who many players saw as a grumpy, grouchy old man. In truth, he only acts this way if the player takes dark side options. If they play light side and talk to Vrook, he'll compliment them on their actions. By the time of [[VideoGame/KnightsOfTheOldRepublicIITheSithLords the sequel]] however, {{Flanderization}} sets in and he just hates you regardless of how well you act.
** By the time of ''VideoGame/StarWarsTheOldRepublic'', Revan, the protagonist of the first game, has clearly gone insane from his 300 years of captivity. At first, he takes over an old battle station and cooks up a plan to [[OmnicidalManiac wipe out 98% of the Imperial population]] (and likely, a good chunk of the Republic's population in the process). Then he returns, waging war on both the Republic and the Empire as the leader of a fanatical cult.
* A minor example in ''VideoGame/FarCry4''. CIA agent Willis Huntley, a major character around the mid-point of [[VideoGame/FarCry3 the previous game]], shows up again to give new protagonist Ajay a couple missions. These missions turn out to be [[spoiler:eliminating other CIA assets in the area to remove evidence of the CIA's presence in Kyrat, after which he throws Ajay out of his plane, leaving him to be captured by the guards of the person whose lieutenants (the aforementioned other CIA assets) he just killed.]]
* In ''VideoGame/TimeCrisis'', Robert Baxter was one of the player characters in the second game. [[spoiler: Then in the fifth, he becomes the BigBad.]]
* ''VideoGame/DawnOfWar 2: Chaos Rising'' introduces the Chaos faction, as well as a KarmaMeter that determines which of your characters is slowly falling to Chaos. [[spoiler:If you keep everyone pure, the traitor will be the MissionControl guy, but canonically Avitus turns traitor.]]