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 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.'''

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!!Examples

[[foldercontrol]]

[[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 ''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 ''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.]]

[[/folder]]

[[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, 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 the SilverAge status quo, whether the universe was ready or not.
*** 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]]]].
** [[{{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.

[[/folder]]

[[folder: Fan Fiction ]]

* Inverted in ''Fanfic/ThePrayerWarriors'', [[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.

[[/folder]]

[[folder: Film ]]

* In the original ''Film/RoboCop1987'', the 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. As writer Creator/PeterDavid noted, the only reason for the betrayal was the movie's screenwriters' need to [[http://www.peterdavid.net/2011/12/19/movie-review-mission-impossible/ destroy heroes.]]

[[/folder]]

[[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 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]].

[[/folder]]

[[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 ''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, orhcestrating 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.

[[/folder]]

[[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]]

[[folder: Videogames ]]

* [[EvilWeapon 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 diabolical "Dr. Clark"]] we heard about in the first game was the sweet and flighty Para-Medic.
* 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.]]
* ''[[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 ''SoulCalibur IV''; where she's made to defend 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 [[WellIntentionedExtremist wants tranquility, order and peace... by freezing the entire world solid]].
* Vladimir Lem in ''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."''
* ''{{Contra}}: Shattered Soldier'' reveals that Blood Falcon is actually Lance, who was player 2 of the original game. [[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.
* [[VideoGame/{{Prototype}} Alex Mercer]] becomes the BigBad in ''VideoGame/{{Prototype 2}}'' after crossing the DespairEventHorizon. The fandom has been [[BrokenBase split]] over this.
* ''WorldOfWarcraft'' has gone ''hard'' on various characters from the WarcraftExpandedUniverse in order to turn them into bosses which may be killed for loot. Perhaps the most jarring case of this being turning Sylvanas from someone who would lay her life down for her kingdom to a quasi-fascist faction leader with a personality cult.
** Garrosh Hellscream could be the poster boy for this trope for Warcraft. 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'', to gaining some character development in ''Cataclysm'', and then finally settles on becoming the main antagonist of ''Mists of Pandaria'' when he gets hit hard by the VillainBall.
*** What makes this even more jarring is that Garrosh seemingly drug the ''entire orcish race'' down with him. There are a grand total of ''three'' orcs who are not villains or on the villains' side in ''Mists'': Thrall, Eitrigg, and Saurfang.
** 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, 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.]]
* ''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.]]

[[/folder]]

[[folder: Western Animation ]]

* In ''WesternAnimation/BeastMachines'', [[spoiler: former Maximal Rhinox turns into Tankor.]] It was intended to be genuine turn towards Megatron's way of thinking - that series seemed to make a ''point'' of making everyone the SameCharacterButDifferent - but ultimately it moved away from that extreme. It was still a shock, because [[spoiler: we'd thought Tankor had the IQ of dirt until he revealed he was a {{Chessmaster}} and only pretending to still be the DumbMuscle Megs had tried to reprogram him into.]]
* In the first episode of ''HomeMovies'', Brendon makes [[ShowWithinAShow a pair of cop movies]] that both play this trope straight and invert it (the hero from the first movie becomes the villain of the second movie while the DirtyCop villain of the first movie rejoins the force and becomes the hero of the second movie).
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