History Main / BigBadFriend

* In ''LightNovel/IsThisAZombie'', Eucliwood Hellscythe considered the King of Night to be her friend still, despite him unleashing a lot of megalo (demons) into the city to harm people and her new friends. [[spoiler:He wanted to die, since he became an immortal zombie to serve her, but she wouldn't do it.]]

* In ''LightNovel/SwordArtOnline'', Kirito eventually realizes that [[spoiler:Heathcliff, head of the most successful guild in the game,]] is actually Kayaba Akihiko, the man who trapped them there in the first place.

This is a '''Spoiler Trope''', so beware.

** As of chapter 96, [[spoiler:Crona]] is stepping up to the role too, setting their aims on absorbing the Kishin himself.

* ''Literature/ChrysalisRinoZ'': When Tungstant realises that the [[FascistsBedTime Torpor Police]] have to have ''modified the fortress'' to have space for all the ants they're taking and giving a good night's sleep, she rushes to her partner, Cobalt, to warn her of the dire news. Cobalt tries to reassure her that the fortress plans aren't secret, surely the torpor enforcers would be making sure that their changes aren't going to bring things crashing down, but Tungstant won't calm down, and can't understand why Cobalt isn't getting upset along with her. Until Cobalt murmurs, "You really should have gone to sleep," and Tungstant is knocked out for her mandatory eight hours' rest.

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* ''VideoGame/TheTestamentOfSherlockHolmes'' implies that Sherlock Holmes is this to Watson, as it drops hints that the famous detective might be the mastermind of the murders committed throughout the game. Watson's deteriorating friendship with Holmes is an ongoing plotline. [[spoiler: Holmes is innocent, of course, but he's doing it deliberately. Moriarty is framing Holmes for the crimes, and Homes is intentionally acting suspicious to keep Moriarty's attention off of Watson.]]
* ''VideoGame/NocturneRebirth'' has [[spoiler:Khaos]], who Reviel considers a friend despite the former scheming against him and trying to destroy/recreate the world, which is why he tries to get his friend to pull a HeelFaceTurn. [[spoiler:Unfortunately, the BigBad ends up committing suicide upon defeat because he was that desperate to enact his plan.]] TheDragon, [[spoiler:Shylphiel]], states that [[spoiler:Khaos]] was likewise fond of Reviel, Luna, and Ristill despite his antagonism.
* ''VideoGame/{{Scorn}}'': The Parasite, which latches itself onto Scorn Guy and gives him the ability to heal himself, as well as turning into a LivingWeapon Scorn Guy uses to fend off other monsters. One would think the Parasite is actually helping Scorn Guy through his journey...until you realize the Parasite is gradually draining Scorn Guy's health throughout the game and transforming his body into a meaty monstrocity. It isn't long before Scorn Guy realizes what's happening and [[spoiler:uses a machine to rip the Parasite off his body before it kills him or fully renders him immobile]].
* ''VideoGame/TheLegendOfHeroesTrailsOfColdSteel'' has [[spoiler: Crow]]. Throughout the game, Class VII has been antagonistic against a group of terrorists called the "Imperial Liberation Front" whose leader is a man called "C". Turns out that said leader [[spoiler: is Crow]] whose room is just across [[TheHero Rean's room.]] He doesn't give out his reasons until the second game as to why he did his terrorism acts.
* ''VideoGame/WarriorsOrochi 4'' introduces [[spoiler:Perseus]], Zeus' half-mortal son, who aids the coalition in confronting Ares and Athena. He's also a mentor to Yukimura, Naotora, Guan Yinping and Zhao Yun when they obtained their bracelets that activate their deified forms. He suddenly goes missing which prompt the coalition to find him no matter what. [[spoiler:It turns out that Perseus is actually Loki, the Norse god of trickery, who wants to bring his master, Odin, to the world by instigating a war between the humans and gods which forces them to activate the bracelets]].
* ''VideoGame/LoserReborn'': One of the [[BigBadEnsemble Big Bads]], the Cultist, is the reincarnation of the protagonist's friend from their previous lives. He wants to destroy the RPG world in order to wake the protagonist from their coma. The protagonist can choose to either side with the Cultist or fight him in the endgame.
* ''VideoGame/TheLastStory'': [[spoiler:Dagran, the main character's best friend and the looked up to and respected leader of their mercenary group turns out to have been TheManBehingTheMan, manipulating both Lazulis Island and the Gurak into re-starting their war, both as a way for him to get power and knighthood for himself and his group and to fulfill his goal to murder General Ashtar. While he claims that he always only saw them as pawns for his long plan to get revenge on the man who killed his family, it's implied that he truly did care for their friends.]]
* ''VideoGame/FireEmblemThreeHouses'': [[spoiler:Edelgard]] is this within the Silver Snow route, as they spend just under a year working alongside Byleth in part 1 of the game before they reveal themselves as the [[TinTyrant Flame Emperor]] in chapter 11 of the game. [[spoiler:Of course, if you are absolutely fed up with the [[PathOfInspiration Church of Seiros]] and their KnightTemplar tendencies, you can choose to side with her instead, leading to the Crimson Flower route.]]
* ''{{VideoGame/Kirby}}'': [[VideoGame/KirbySuperStar Marx]] and [[VideoGame/KirbysReturnToDreamLand Magolor]] start their games off by being friends with [[TheHero Kirby]], but they secretly [[ManipulativeBastard trick Kirby into doing their bidding,]] and as a result, they become the FinalBoss of their respective games.
* ''VideoGame/YsSeven'': Adol befriends [[spoiler:Tia, a resident of Old Town whose friend Maya is suffering from Iskan Fever. Unfortunately, the fever is caused by the imbalance of Dragon Energy in Altago, so Tia takes up her role as the Maiden of Demise and seeks to destroy and restart all life on Altago in the hopes that Maya will be reincarnated under better circumstances. Despite this, her friendship with Adol is genuine and Scias states that she would be sad to kill him.]]

** ''VisualNovel/DanganronpaTriggerHappyHavoc'': Since every case is composed by a murder committed by one of the people who you had to live for a little while, while most case end up showing the murderer as sympathetic in their motives, some times they do come off as cold blooded killers, such as [[spoiler: Celestia, who killed Hifumi and Ishimaru to get out of the school with the money offered by Monokuma]], [[spoiler: Mikan, who killed Ibuki and Hiyoko after regaining her memories as a member of Ultimate Despair]] and [[spoiler: Nagito, who not only essentially caused the first murder sets up his own death to be unsolvable, on a try to get everyone besides Chiaki killed.]] After [[spoiler:Celestia's]] execution, Makoto notes that since the culprit killed his friends, he can't pity her, but acknowledges once thinking of her as a friend, which gets him into pitying her anyway and blaming Monokuma for her FaceHeelTurn and resulting death.

*** The last case reveals that [[spoiler: Hinata and everybody else but Chiaki are the Remnants of Despair, a group of Ultimate Despair that served directly under Junko and are trying to destroy the world, though none of them have memories of that]].
*** [[spoiler:Chiaki]] is a subversion, as [[spoiler: even though she was the traitor, she was working for the Future Foundation, who was trying to help them. During the aforementioned incident in which she is set up as Nagito's killer, she [[HeroicSacrifice does everything she can to ensure that she's convicted (and executed) for it]], even though she's unable to actually come out and reveal herself as the "traitor"]].

* Defied in WebAnimation/PerfectKirby with Bill, the BigBad of the first installment. Kirby considers Bill an annoyance, and while he is surprised by Bill being the Xbox smuggler, he rejects Bill's claim that they're friends.

* [[spoiler:Kevin]] in ''WebVideo/TribeTwelve'' is [[spoiler:secretly [[DragonInChief The]] [[FourEyesZeroSoul Observer.]]]] No one is happy to hear it.

** In ''Cult of the Conductor'', [[spoiler:Simon starts out as Grace's closest friend, but as book 3 progresses, his refusal to change the Apex's violent ways drives a wedge until he eventually tries to usurp and kill her.]]

* ''Franchise/AvatarTheLastAirbender:''
** In ''WesternAnimation/AvatarTheLastAirbender'', Fire Lord [[GreaterScopeVillain Sozin]] was best friends with Avatar Roku growing up and the two considered each other brothers. The two became distant due to Roku's duties as the Avatar and Sozin's plans for conquest, and Sozin betrayed him as soon as he had the chance. Notably, however, on his deathbed Sozin [[WasItReallyWorthIt took the time to reflect on his actions]] and [[MyGodWhatHaveIDone realized that he did regret what he had done]], only to bitterly note it was far too late for apologies to make things right.
** Sequel series ''WesternAnimation/TheLegendOfKorra'' has Varrick for Bolin. He did betray him and his friends, intended to use Unalaq's plan for his own selfish benefit, but Bolin still respected him and was still willing to accept his help against their real enemies. This seemed to become a more legitimate, trustworthy friendship as the series progressed, however.
* ''WesternAnimation/CleopatraInSpace'' reveals that the evil intergalactic conqueror Octavian is actually [[spoiler: Cleo's childhood best friend Gozi, who under unfortunate circumstances, survived 30,000 years and become a villain.]] He actually doesn't want to fight Cleo and offers her to join him in conquest, but she rejects the offer.
* ''WesternAnimation/DannyPhantom'': Danny's ArchEnemy Vlad Masters is this to Danny's father Jack, who was his best friend in college. Not that Vlad makes much of an effort to hide how much he hates Jack in the present (which [[TheDitz Jack]] remains oblivious to), except when he wants something from him, but he does a good job of convincing everyone other than Danny and co. that he's not ''evil''. [[spoiler: At least until the GrandFinale. When Jack found out he'd been played he was...[[SugarWiki/MomentOfAwesome not happy]].]]

** Most notably, Gene to Tony. Gene was the Mandarin the entire time and caused the plane crash that resulted in Tony wearing the arc reactor and [[spoiler: Howard Stark being presumed dead. It is revealed that Gene kidnapped him to get the Makulan ring he found and force him to help Gene find more.]] Gene did have some feelings of friendship left for Pepper, but did not let that stop him from achieving his goals.
** Subverted with the Living Laser, who [[spoiler: was split into two- a good one and an evil one. Tony thought his friend had betrayed him before discovering the truth.]]

* Dr. Benton Quest in ''WesternAnimation/JonnyQuest'' seems have a serious problem with friendships; often whenever he pays a visit to friends or even acquaintances, they are often turn out to be psychopathic MadScientist types or minions of [[BigBad Dr. Zin]] who are eager to kill him and his family.

* ''Literature/TreasureIsland'': Long John Silver, Jim Hawkins's mentor figure and the local MagnificentBastard, is probably the most famous example of this trope. [[spoiler: So much that he manages to get away with it in the end.]]
* In Creator/AgathaChristie's ''Ordeal by Innocence'', [[spoiler:the former nanny is this to Philip Durrant, warning him to stop prying into the murder of his mother-in-law, which she committed on behalf of the victim's delinquent son. She murders Philip to cover her tracks.]]
* In ''Literature/{{Dragonlance}}'', Kitiara in her final moments is {{mind rape}}d when she discovers that her servant, Lord Soth intends to kill her and make her [[FateWorseThanDeath serve him as his banshee for all eternity.]]
* Robert Harris' ''Literature/{{Fatherland}}'', where [[spoiler:Xavier's old friend Max Jaeger]] turns out to be the source of the SS's inside information.
* Fidelias to Amara in the ''Literature/CodexAlera'' series. Not much of a spoiler, though, since his real allegiance is revealed within the first couple of chapters of the first book.
%%* Every Creator/DanBrown novel features this trope where the friend or trustworthy boss turns out to be the ''BigBad''
%%** [[spoiler:Carlo Ventresca]] in ''Literature/AngelsAndDemons''.
%%** [[spoiler:Trevor Strathmore]] in ''Literature/DigitalFortress''.
%%** [[spoiler:William Pickering]] in ''Literature/DeceptionPoint''.
%%** [[spoiler:Sir Leigh Teabing]] in ''Literature/TheDaVinciCode''. [[spoiler:There's actually a few betrayals and friend-turned-villains here including Andrernet, Legaludec and to a lesser degree Bezu Fache]].
* In ''Literature/{{Tunnels}}'', the BigBad turns out to be [[spoiler:the protagonist's little sister]].

* ''Literature/AmericanGods'': One of Shadow's old friends, [[spoiler:Low-Key Lyesmith from his stint in prison]], is actually [[spoiler: Mr. World/Loki]]. This becomes especially trying it involves [[TheMentor Mr. Wednesday]], [[spoiler:he turned out to be working with Loki the entire time, working to manipulate both sides into a devastating war]].
* In ''{{Literature/Aristoi}}'', [[spoiler:Zhenling]] was part of the BigBad's plan to crack Gabriel's encryptions all along.
* In ''Literature/TheUnderlandChronicles'', to all appearances, [[spoiler:Henry's affection for his cousin and his offer to rule with her are sincere.]]
* The Thing in Tamora Pierce's ''Literature/{{Mastiff}}''.

* In books 5 and 6 of ''Literature/TheSagaOfDarrenShan'', Darren's discovery and exposure of [[spoiler: Kurda's treason]] plays out like this, although he really is more of a WellIntentionedExtremist.
** Played straighter in book 9 with [[spoiler:Steve Leonard, who... [[AxCrazy isn't.]]]]

* The first Stuart Gibbs ''Literature/SpySchool'' novel has the hero realizing that [[spoiler: his PluckyComicRelief CynicalMentor is TheMole]], something that becomes a LateArrivalSpoiler for the rest of the series.

** In the final episode of Season 4, [[spoiler:Ruby]] reveals to Sam that she had been collaborating with Lilith the whole time just as [[spoiler:Lucifer rises.]]

%%* Dr. Wily is this to Light, in Music/TheProtomen.

* ''Franchise/{{Persona}}'':
** This role is played with in ''VideoGame/Persona3'', with [[spoiler: Ryoji Mochizuki. He certainly acts as a friend to the protagonist, which is played up in the BigDamnMovie, but he isn't even a social link in the original game, and while he's the closest thing to a BigBad in the game, he's really more of an AntiVillain, having no choice as to whether he destroys the world or not. This is made even more apparent in the female route, where he acts as a social link, and is a romance option.]]
** ''VideoGame/{{Persona 5}}'': [[spoiler:Goro Akechi, one of the characters the Protagonist befriends over the course of the game, turns out to be TheHeavy for the bad guys, and the one ultimately responsible for the formation of TheConspiracy.]]
* This is the case with ''VideoGame/DigimonStoryCyberSleuthHackersMemory'': Your friend Yu is actually K, the hacker that stole your identity, then spends the game "helping" you recover your account by sending you on a wild goose chase. Yu was hoping that you would become more dependent on K's advice, eventually isolating you from everyone and ensuring that you two would be friends and partners forever.
* Flipped around in ''VideoGame/DragonAgeOrigins'': The villain Loghain thinks that his king and son-in-law is a Big Bad Friend who is selling out the kingdom to the same empire that his father and Loghain expelled from the country just one generation ago. Thinking the king has already made his FaceHeelTurn and become TheQuisling, he betrays him and takes control of the kingdom himself.
** ''Return to Ostagar'' reveals that [[spoiler:the king was indeed planning to divorce Loghain's daughter Anora and marry the Empress of Orlais had he survived the battle, which if Loghain is a party member at the time has him both vindicated and furious that he was ''[[TheExtremistWasRight right]]'' all along.]]
** Subverted again in ''VideoGame/DragonAgeII'', where Cassandra is [[ConspiracyTheorist convinced]] that Varric's friend Hawke was the BigBad responsible for everything and went to Kirkwall specifically to start the Mage-Templar War that is currently sweeping Thedas, when in reality, they were simply the RightManInTheWrongPlace and were swept up in events far outside of their control. Played straight with [[spoiler:Anders, however, who blows up the Kirkwall Chantry, killing scores of innocents, to incite a mage rebellion, ultimately leading to said war]].
** And then ''VideoGame/DragonAgeInquisition'' gives us [[spoiler:Solas, a.k.a. the [[GodWasMyCopilot elven god of rebellion]] [[TheTrickster Fen'Harel]]. Not only was he indirectly responsible for the Breach, he has been manipulating the Inquisition the entire time, and is actually planning to destroy the Veil, merging Thedas and the Fade, which would most likely kill every living being on the planet. If he likes the Inquisitor, he'll be deeply reluctant about it and challenge the Inquisitor to prove him wrong, but if he doesn't, then he'll have no regrets]]
* ''[[VideoGame/Onmyoji2016 Onmyōji]]'': [[spoiler: '''[[NiceGirl Yaobikuni]]''', my God, [[YamatoNadeshiko Yaobikuni]]. She's been ''seriously'' nice and ''seriously'' helpful to the rest of the main quartet before the revelation that everything she does is only part of her plan to serve the [[GreaterScopeVillain Yamata-no-orochi]] hits them ''hard'']].

* In '' VideoGame/TalesOfSymphonia'', [[spoiler:Mithos]] is quick to befriend the party once they meet him, and he becomes especially close with [[spoiler:Genis]]. Once [[spoiler:Genis]] finds out that his "friend" isn't just an enemy, but [[spoiler:the leader of Cruxis and BigBad of the game]], he reveals that he had his suspicions, but didn't want it to be true, and spends much of the rest of the game struggling with his feelings of betrayal, but thinking of [[spoiler:Mithos]] as a friend on some level..
** [[spoiler:Kratos]] is set up as another such case. Initially, the character doesn't seem all that close to anyone in the group, having supposedly joined [[spoiler:only for the money]] (which is actually a lie), but gradually becomes something of a mentor to Lloyd, if fairly cynical. The group takes it hard when they realize [[spoiler:Kratos]] has betrayed them, but late in the game, [[SubvertedTrope it turns out that]] he was GoodAllAlong, and Lloyd forgives [[spoiler:Kratos]] after defeating him in a final duel.
%%** In ''Dawn Of The New World,'' [[spoiler:Emil and Richter]] without a doubt.
%%* ''Franchise/{{Castlevania}}''

%%* The possibility is explored in ''VideoGame/{{Bomberman}} 64''. [[spoiler:the friend is indeed the big bad]].
* [[spoiler:Special Agent Kato]] the third and final BigBad in ''VideoGame/ShadowHeartsCovenant'', doesn't let a little thing like wanting to destroy the world ruin the good friendship he has with Yuri. He even encourages the heroes to stop him if they truly believe they've got the right moral standpoint compared to his.
* [[spoiler:Joshua]] in ''VideoGame/TheWorldEndsWithYou''. [[spoiler:You actually have him as a member of your party for 1/3 of the game,]] as well as a cutscene that starts out short but is slowly revealed (an attempt to confuse the player as to whether [[spoiler:Neku's killer]] was him or the Reaper, [[spoiler:Minamimoto]]). The game switches itself up on you: It intentionally makes you suspect that [[spoiler:Joshua did it]], then reveals it to be [[spoiler:Minamimoto]] with some rather convincing evidence, even so far as to make you think that [[spoiler:Minamimoto could be the final boss, especially after he revives himself]]. Then, the end of the game does a 180 and reveals that [[spoiler:Joshua was not only the killer, but the Composer of the game as well: He killed Neku (who could use any pin) so that Neku could take his place in the Game that would determine Shibuya's fate]].

** [[spoiler: Vossler]] from ''VideoGame/FinalFantasyXII'' fights alongside you for a chunk of the game, but sells you out to the Archadian Empire afterwards on the belief that [[spoiler: it would be better to surrender to stop the bloodshed instead of continuing a seemingly fruitless rebellion. He's immediately given the StrawTraitor treatment, fights you as a boss later on, and then dies dramatically on an exploding warship.]]

* ''VideoGame/MetalGear''

** The plot point is repeated again for ''VideoGame/MetalGearSolid'', wherein [[spoiler:radio contact Master Miller turns out to have been DeadAllAlong, with the Master Miller you talked to being Liquid Snake in disguise.]]
%%* In ''VideoGame/{{Sonic and the Black Knight}}'', [[spoiler: Merlina]]

* In ''VideoGame/DungeonSiege 2'', [[spoiler:the Azurite Scholar that has been helping you throughout the game turns out to be the Overmage of the Cinbri, who has been manipulating both you ''and'' the BigBad in order to reshape Aranna in his image.]]
* [[spoiler: Fasti, who is actually Mobius,]] is the BigBad of ''VideoGame/AgarestSenki2''. Until [[spoiler: he]] does TheReveal, [[spoiler: he]] was the resident [[spoiler: TheSmartGuy.]]
* In ''VideoGame/EarthBound1994'', Pokey claims that Ness is his best friend, and you can tell a cop that you're both friends, too... until he does a FaceHeelTurn. Though, that would make him TheDragon Friend... [[spoiler: Until ''VideoGame/{{Mother 3}}''. In that game, it shows that he really did consider Ness a friend; he cherishes the latter's weapon, the "[[ImprobableWeaponUser Friend's Yo-Yo]]" and keeps a shrine to him in his headquarters.]]
* In ''VideoGame/{{Rosenkreuzstilette}}'', [[spoiler:Iris is considered like a kid sister to the rest of RKS, including Tia. What they don't know is that she's really the BigBad who's making RKS fight against the [[UsefulNotes/HolyRomanEmpire Holy Empire]] ForTheEvulz. She eventually reveals to Tia who she really was and the real reasons for the war, and that she really did all that for both said reason and [[GodhoodSeeker to become god of the world]]. That's where none of RKS trusts her anymore]].
* At the end of ''VideoGame/BeyondDivinity'', [[spoiler:its revealed that your only ally throughout the game, the unnamed Death Knight, is actually, Damian, the BigBad of the ''Divinity'' series.]]
%%** [[spoiler:[[{{Subverted}} But it's all a ruse, though]].]]

* In the ''VideoGame/{{Lufia}}'' series, a common plot element is a certain character being [[spoiler: Erim, the Sinistral of Death. In ''VideoGame/LufiaAndTheFortressOfDoom'' it was Lufia herself, in ''VideoGame/LufiaIIRiseOfTheSinistrals'' it was Iris, and in ''VideoGame/LufiaTheLegendReturns'' it was Seena.]] Often, this character is not even aware of their true identity.
%%* ''VideoGame/CallOfDutyModernWarfare's'' BigBad:
%%-->'''[[spoiler:General Shephard]]:''' [[FalseReassurance Good.]] [[WhamLine That's one less]] [[YouHaveOutLivedYourUsefulness loose end.]]
* Happens several times in the ''VideoGame/GrandTheftAuto'' series:
** In ''VideoGame/GrandTheftAutoViceCity'', [[spoiler:Lance Vance]] sells out Tommy Vercetti to Liberty City mafioso [[BigBad Sonny Forelli]] in the final mission out of opportunism because he felt he was being sidelined by Tommy in the Vercetti criminal empire.
** In ''VideoGame/GrandTheftAutoSanAndreas'', [[spoiler:Big Smoke and Ryder]] betray the Johnsons to corrupt police officers Frank Tenpenny and Eddie Pulaski to get rich off the drug trade.
** [[spoiler:Billy Grey]] in ''VideoGame/GrandTheftAutoIVTheLostAndDamned''. He ultimately decides to sell out the entire Lost MC for his freedom; however, Johnny Klebitz infiltrates the prison and personally executes [[spoiler:Billy]] before he can testify.

* ''VideoGame/SpacePiratesAndZombies'' has [[spoiler:Don who turns out was a zombie leader/commander all along, and was leading you to the core to unleash the zombies.]]
* [[spoiler:Pavel]] in ''VideoGame/MetroLastLight'' is Artyom's travel companion for a major part of the game and the two end up saving each other's life several times before they finally make it back to a civilized station where they are safe to relax and stock up on supplies before they each make their way to their respective homes. [[spoiler:Over a farewell meal, he tells Artyom that he's not just forced to be a soldier for the Communists, but actually believes in their principles. At that moment two communist officers appear behind him and it turns out that he's not just a simple scout, but a Major who was tasked to capture Artyom and just happened to end up in the same Nazi prison after his team was killed. And he just had been spiking your drinks.]]
* [[spoiler:Livia]] in ''VideoGame/AlphaPrime''. At the end, it's revealed that they're not just TheMole, but were the Company's agent that orchestrated the plot in the first place. This also leads into [[spoiler:[[TheBadGuyWins the bad guys winning]]]].
* The FinalBoss of ''VideoGame/KnightsOfTheOldRepublicIITheSithLords'' is one of your party members and also the person who's been [[EvilMentor mentoring and advising]] the player character throughout the game. Whether they actually qualify as EvilAllAlong, though, [[WellIntentionedExtremist is left up to the player to decide]].
* In ''VideoGame/SpiderManMilesMorales'', [[GadgeteerGenius the Tinkerer]] is Miles' ChildhoodFriend Phin who's desperately trying to get revenge on the EvilInc Roxxon for killing her brother by any means necessary.

* ''VideoGame/Halo5Guardians'': [[spoiler: Cortana]] is [[CameBackWrong back and evil]] but still very devoted to Master Chief. [[spoiler: The difference in her warm encouragement to John 117 and bitter hostility to the new {{Deuteragonist}} Locke is very noticeable.]]
* It turns out that the [[HeroKiller Parkour Killer]] in ''VideoGame/MirrorsEdge'' is [[spoiler:Faith's best friend Celeste, who believes the Runner's days are numbered and is fine with helping the police capture all her old Runner buddies to save her own sorry ass.]]
* ''{{VideoGame/Anachronox}}'': In the end, [[spoiler:Grumpos, the second character in your party, looks like he's going to destroy the key to open the portal, but instead]] reveals he's with the bad guys the whole time and opens the portal for them.
* ''VideoGame/{{KOLM}}'': In the second game [[spoiler:Father]], who'd seemed to be an ally, turns out to have been working with Mother the whole time and tosses Robbie aside when he succeeds in bringing Sister to him.

%% Administrivia/ZeroContextExample entries are not allowed on wiki pages. All such entries have been commented out. Add context to the entries before uncommenting them.

* All over the place in ''Manga/AttackOnTitan''. Eren learns that [[spoiler: Annie Leonhart, the girl that taught him how to fight, is really the Female Titan responsible for slaughtering his squad mates.]] Not long after that, he learns [[spoiler: that [[TheQuietOne meek]] Bertolt Hoover and TeamDad Reiner Braun were the Colossal Titan and Armored Titan all along. And therefore, indirectly responsible for a good majority of the death in the series, including that of his mother.]] To say he's [[YouMonster less]] [[RoaringRampageOfRevenge than]] [[YouKilledMyFather thrilled]] is an understatement. For an extra twisting of the proverbial knife, all are presented as [[TragicVillain sympathetic]] and [[BecomingTheMask genuine]] in their attachment to the people they've betrayed.
** [[spoiler: After the TimeSkip Eren himself becomes this, although the "friend" has been averted dramatically since then]].

* In a filler arc, Manga/{{Naruto}} learns that the old man he often ate with at the ramen shop is actually a ninja from a village that had been destroyed, who seeks revenge against the Leaf Village. [[spoiler:Interestingly enough, his friendship with Naruto actually ''was'' genuine, and he replaced the deadly explosive tags across the village with harmless ones, intending it as a scavenger hunt similar to the games he played with his son]].
** Near the end of the series, [[spoiler:Sasuke becomes this: after thwarting Madara Uchiha's plan to take over the world with a superpowerful genjutsu, Sasuke reveals that he plans to kill the Kages, trap the tailed beasts in satellites, and start a revolution and taking over the world himself.]]

* After tre Arachnophobia arc in ''Manga/SoulEater'', it turns out that [[spoiler:Justin Law]] had gone through the first phase of this, but afterwards... well, [[spoiler:turns out that Law worships Asura, not Shinigami-sama, is an extreme misogynist, likes to be playing HoYay with his longtime apparent enemy, and more than likely helped set up Kid to be kidnapped by the arc's BigBad {{Chessmaster}}.]] So, he subverted this while acting TheMole. He might still like Stein, though, because [[spoiler:he did retreat before injuring him]].

* ''Anime/HugttoPrettyCure'': [[spoiler:George Cry, president of the Dark Tomorrow Company and the one responsible for creating a BadFuture through TimeCrash-ing to a halt, is actually a friend of Future Hana, who's suffering and death motivates him to stop time at all costs, even if it means subjecting the Hana of the present timeline through extreme psychological torture. However, it should be noted that he never reveals this information to her in the slightest throughout all of their confrontations, so for all Hana knows, he's just a villain in every sense of the word.]]
* In ''Literature/PsychicWars'', not one, but two [[spoiler:lovers of the main characters are demons, one of them being the BigBad of the story.]]

* This happens to ComicBook/SpiderMan with alarming regularly. His friends and co-workers are guaranteed to either die, go mad, or both.
-->'''[[http://asitecalledfred.com/comics101/69.html Comics 101]]:''' ''[[ComicBook/TheCloneSaga [T]he Jackal]]'' was merely the latest in a long tradition in ''Amazing Spider-Man'' in which nearly everyone in Peter Parker's life either becomes a villain or is related to a villain in one way or another. Need examples? First girlfriend Betty Brant? She married Ned Leeds, who eventually became the Hobgoblin. Schoolmate Liz Allen? Her brother was the Molten Man. JJJ? His son becomes the Man-Wolf. Peter Parker's parents? Turns out they were killed by the Comicbook/RedSkull. The list goes on and on (and on). In a world like this, one of Peter's college professors becoming a supervillain makes perfect sense.
* ''ComicBook/BlazeOfGlory'': [[spoiler: Marcel Fournier]] turns out to be a spy for the nightriders.
* Hartigan in ''ComicBook/SinCity'' has one of these, his partner Bob, who shoots Hartigan in the back to keep him from killing Senator Roark's pedophile son. There are apparently no hard feelings on either side, and Bob gives Hartigan a lift back to town after he gets out of jail (this only happened in the film; in the comic the guy who gives Hartigan a lift is a different ex-colleague, and he doesn't see Bob again).
** Bob is later ([[AnachronicOrder or earlier, depending on your point of view]]) killed by a different partner, whom Ava Lord had dug her talons into.
* Maxwell Lord to the [[Franchise/JusticeLeagueOfAmerica JLI]]. Despite killing [[ComicBook/BlueBeetle Ted Kord]] in the build-up to ''ComicBook/InfiniteCrisis'', Max still views them as his friends and warns them to stay out of his way, even telling ComicBook/BoosterGold that killing ComicBook/BlueBeetle wasn't easy for him.
* [[spoiler: Adrian Veidt]] in ''ComicBook/{{Watchmen}}'' is introduced as a former team member of the other second-generation characters, although no longer especially friendly with them, but is actually the Big Bad of the comic, plotting to [[spoiler:commit a massacre in order to fake an alien invasion and unite humanity.]]
* In ''ComicBook/{{Zero}}'' [[spoiler: Robert]] is Ginsberg Nova.

** [[spoiler: Maika's lover Tuya]] turns out to be the one leading the Dusk Court's efforts to hunt down and kill Maika.
** Master Ren turns out to be spying on Maika for his cat superiors, who know all about her lineage and the [[EldritchAbomination Monstrum]] inside her, and seem to have their own agenda. [[spoiler: When they decide to abduct [[MoralityPet Kippa]], however, he turns on them.]]
* ''ComicBook/LockeAndKey'': In his false identity of Zac Wells, [[BigBad Dodge]] befriends the Locke children (particularly Tyler and Kinsey, the latter of whom he starts dating) so that he can use them to find the [[ArtifactOfDoom Omega Key]].

* [[spoiler: Grunnel]] in ''Fanfic/WithStringsAttached''. He genuinely likes the four and is fascinated by what they have to say about Earth. But when [[spoiler:Brox]] comes up with a use for Paul that [[spoiler: Grunnel]] knows Paul won't agree to, [[spoiler: Grunnel]] quite readily backstabs the four to ensure Paul's participation in [[spoiler: Brox]]'s scheme. As he says to Ringo: "[[spoiler: Brox]] is my friend. You are not my enemies. Do you understand the difference?" Yet he prevents [[spoiler: Brox]] from killing George and Ringo because he likes them.
* [[spoiler: Drew]] in the ''Series/HannahMontana'' fic "I Didn't Sign Up for This". She is quick to befriend Miley and dates Lilly but in the last chapter, she is revealed to be a murderous sociopath that cares about [[YouHaveOutlivedYourUsefulness no one but herself.]]
* In the side stories to Fanfic/MGLNCrisis, it turns out that [[spoiler:Racquel Benna/Zettin, the fruit vendor Fate knows was actually a scientist who worked alongside Precia and Scaglietti, creating a clone of Clyde Harlaown who served to impregnate Precia with Alicia. Racquel said she moved near Fate hoping to tell Fate the truth one day.]]
* [[spoiler: Phoenix Wright himself to Mia Fey]] in the fangame ''VideoGame/TurnaboutOfCourage''.

* The entire plot of the ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' fanfic ''FanFic/InnerDemons'' revolves around a prophecy that Twilight Sparkle will be consumed by her [[EnemyWithin inner darkness]] and become Equestria's EvilOverlord. This happens within a matter of chapters, and the rest of the story is dedicated to her trying to kill the rest of the Mane 6, and them trying to fight and/or redeem her (until {{the climax}}, there's a bit of debate among them).
** As another Twilight Sparkle-related example, ''FanFic/PagesOfHarmony'', Twilight is driven by a desire to extract the Elements from her friends by [[spoiler:capturing and murdering them in various ways specific to their Elements]]. Though much like Light in ''Manga/DeathNote'', she appears to believe she's doing it for the greater good, and her friends try to get through to her and get her to come to her senses. [[spoiler:She doesn't listen.]]
** Another Twilight Sparkle-related example (these are popular, aren't they?). ''FanFic/DeathNoteEquestria'' has her taking on the role of Light as Kira. She's so determined to defeat L and enforce her vision of justice on the world that she even goes so far as to [[spoiler: engineer Rarity and Pinkie's death as part of her cover]]; she does have a few VillainousBSOD moments along the way, but that hasn't stopped her so far.

* ''Fanfic/FriendshipIsMagicalGirls'': Rainbow Dash and Lightning Dust were friends growing up; when Lightning returns to town, Rainbow is thrilled at the prospect of renewing their friendship. Unfortunately for her, Lightning is a member of the Shadowbolts (the main antagonists of the Loyalty Arc), and has no problem using their friendship to gain information that can be used against the mahoushoujo. When Lightning eventually outs herself as a Shadowbolt, Rainbow is ''pissed'', and then depressed.
* ''FanFic/RosarioVampireBrightestDarkness'': Hokuto serves as such in Act III, pretending to be a friend to Tsukune and the gang and hatching a plan to have them defeat Kuyou when he attacks Yokai Academy, thus proving to the students that they're not {{Fake Ultimate Hero}}es and they really did beat Fairy Tale. As it turns out, Hokuto himself set the whole thing up; he lured Kuyou back to the academy and manipulated Tsukune and co. into fighting him so he could use the chaos as a diversion to steal an ArtifactOfDoom he needed in order to resurrect [[EldritchAbomination Alucard]] and bring about TheEndOfTheWorldAsWeKnowIt, all out of [[OmnicidalManiac sheer]] [[StrawNihilist nihilism]]. While he's not the legitimate BigBad of Act III, that role taken by Kiria, he ''does'' take over the role in Act IV.
* In ''FanFic/ConversationsWithACryptid'', ''two'' people Izuku knew turned out to be dangerous villains. His childhood doctor was a member of [[BigBad All for One]]'s inner circle, and [[spoiler: [[LukeIAmYourFather his absent father is All for One himself]].]]
* In ''FanFic/BookFiveLegends'', ''two'' characters newly introduced (who quickly become friends with Team Avatar) are revealed to be working against the heroes as a BigBadDuumvirate, [[spoiler:adopted siblings Temuji and Fumiko]].
* In ''Fanfic/MadWorldInvaderZim'', Nny is this to Dib, who is totally unaware that his new friend is the SerialKiller he's investigating.

%%* O-Dog from ''Film/MenaceIISociety''.
* ''Film/TheBabysitterKillerQueen'': In the original ''Babysitter'' film, [[spoiler: Melanie]] was Cole's [[GirlNextDoor cute 12 year old neighbor]] and his only friend at school. She even helped him by letting him take refuge at her dad's house when [[BigBad Bee's]] cult was trying to kill him. The sequel is set two years later and does a complete 180º by suddenly making [[spoiler: Melanie]] the cult's new leader, who now seeks to kill Cole herself.
* In ''Film/{{Skyscraper}}'' when Will Sawyer [[spoiler:tells his best friend and former FBI colleague Ben whom he considers a 'brother' that he removed the tablet from his stolen bag and still has it, Ben laments, drawing his weapon on Will revealing he helped orchestrate the terrorist plot on the building but did not mean for his family to get trapped inside]].
* When Michael [=MacCauley=] in ''Film/TheCommuter'' [[spoiler:gets surrounded inside of a derailed train cart with a group of hostages, his best friend and former police colleague Det. Lt. Alex Murphy comes in to negotiate. After a slip of the tongue Alex reveals he is working with the criminals and is responsible for directly evolving Michael but did it to help with his money problems as he thought Michael wouldn't ask any questions]].
* ''Film/SwordOfTheAssassin'': Nguyen Vu's childhood friend, whom Vu believed to be a freedom fighter, [[spoiler: was actually a power obsessed BitchInSheepsClothing who planned on having the entire royal family murdered to cement his rise to power. In the end, Vu deemed him even worse than the current empress, a woman who ordered the execution of Vu's entire family]].

* More than once to Film/JamesBond, though he ought to have expected it. The biggest example is [[spoiler: Alec Trevelyan aka Janus from ''Film/GoldenEye'', who once was James's partner and best friend as well as Agent 006, but after faking his death becomes the BigBad of the movie.]]

%%* The film ''Rogue'' features this as part of it's double-twist ending.
* In ''Film/SnakeEyes'', the best friend of the detective protagonist sets his friend up to cover up the assassination of the Secretary of Defense at the stadium. He's a WellIntentionedExtremist who cooperated with a group of military contractors because of a dispute about a military software system that might be dangerous, which the Secretary wanted to cancel.
* The villain in ''Film/{{Sneakers}}''. "I cannot kill my friend." ''[hands gun to mook]'' "Kill my friend."
* In ''Film/{{Horns}}'' Ig is trying to work out who killed his girlfriend, and if it was truly him. [[spoiler:Turns out his secretly jealous best friend was the killer.]]

* ''Film/TheThirdMan''. [[spoiler:The protagonist is investigating the murder of his friend Harry Lime. It turns out that Harry Lime is alive and engaged in horrible crimes. He's the villain of the story]].

* ''Film/MinorityReport'': [[spoiler:Lamar Burgess is a WellIntentionedExtremist who tries to set up a {{Utopia}} that unfortunately involves a murder. He was also John Anderton's good friend until he was exposed.]]
* ''Film/TheTrumanShow''. Truman's "best friend" since childhood (who is really an actor) at one point appears to truly be listening to Truman's plight and confusion, almost seeming to really want to help his buddy understand the crap that's going on with his life. However, he allows himself to be instrumental in the biggest MindScrew the studio pulls on Truman in bringing his "father" back from the grave. He later leads the hunt to capture Truman once he starts escaping. Earlier drafts and deleted scenes emphasized the actor being torn over doing such a thing to a man he had genuinely come to view as his best friend, and in these drafts he initially redeemed himself by intentionally looking the other way when locating Truman and allowing him to escape.
* ''Film/HotFuzz''. [[spoiler:Danny Butterman, the cop Nicolas befriends is actually in on what is going on, but tries to keep him out of trouble, even going so far as faking his death. Considering that when Nick tries to explain, Danny immediately enters an extreme state of denial and then sends him back to London, it's possible that he ''was'' aware on some level, but subconsciously never connected the dots for the sake of his own psyche. When Nicholas returns to stop the NWA, though, he chooses to join him.]]
* ''Film/BloodWork'': Terry [=McCaleb=]'s [[spoiler:associate, Buddy, happens to be a WellIntentionedExtremist and the serial killer he was searching for all the time]].
* Happened to Hartigan at the beginning of his segment in ''Film/SinCity'', when his partner shoots him in the back to keep him from killing the bad guy. But, you know, he really ought to have seen it coming, what with the partner being played by Creator/MichaelMadsen.
%%* The Creator/JuliaRoberts/Nick Nolte rom-thriller ''I Love Trouble''.
* Textbook example in the Creator/SamuelLJackson and Ed Harris film, ''Cleaner''. Ed Harris is Sam's best friend that helps him but later betrays him.

* In ''Film/LastActionHero'''s [[ShowWithinAShow Movie Within A Movie]], CowboyCop Jack Slater's buddy in the FBI, John Practice, turns out to work for BigBad Vivaldi.
* The hero's partner, played by Kevin Pollock, in ''Film/EndOfDays'' turns out to be in league with the villains.
%%* Edward (not Edmund, like in real life) is this to Detective Harris in ''Kemper: The [=CoEd=] Killer''.
* ''Film/StreetKings''. Detective Tom Ludlow's entire police unit is in on Washington's murder and have gone way too far in their corruption, keeping Ludlow in the dark because of his better morals. Capt. Wander (the prime mover in the whole operation) even admits at the end that despite ordering him killed, he loves Tom more than any of the other guys in their unit and unlike them he is irreplaceable for him. They say goodbye as family before Ludlow shoot his friend.
* In ''Motives'', the lead protagonist is set up for a fall by his best friend. Why? To steal the protagonist wife.
* In ''Film/DarkBlue'', Jack Van Meter sets up Perry's murder, which fails when Bobby is killed instead.
* In ''Film/Another48Hrs'', sequel to ''Film/FortyEightHrs'', Jack's fellow detective, Ben Kehoe, is revealed as a big time drug dealer. The character had been used for some exposition in the first film and it was somewhat given away by having him slick back his hair and wearing a suit in the second.
* [[spoiler:Elijah Price]] is the BigBad of ''Film/{{Unbreakable}}'', [[spoiler:which he reveals only when he and David are starting to become friends near the end. He sees life as the prototype of a story after becoming intrigued by the comics his mother gave him, so he killed hundreds of people in mass disasters over the years to find his antithesis, a real hero. He manipulates David over the course of the film to fill this archetype, not to save people, but to find meaning in his own life.]]
* In ''Film/{{RIPD}}'' [[Creator/KevinBacon Hayes]] turns out to be a dead-o, and organizing the dead's plan to reconstruct the Staff of Jericho.
* In ''Film/TheAmazingSpiderMan2'', Harry Osborn turns out to be this in the end, angered at Peter for refusing to give him his blood so that his disease could be cured. Electro can also count.
* ''Film/CaptainAmericaTheWinterSoldier'': Despite the title, the Big Bad Friend is actually [[spoiler:Pierce towards Nick Fury]], not Bucky Barnes towards Steve Rogers.
* Senator Paine from ''Film/MrSmithGoesToWashington'' admires Mr. Smith's idealism and doesn't want to see him ruined by the political machine that he ends up fighting, though not enough to come clean. [[spoiler: Until the end, that is, when his conscience finally gets the better of him.]]

* ''Film/TheBelievers'': Cal's closest friends turn out to be part of an evil cult that sacrifices children and want him to join them by offering up his own son.
* ''Film/TheFaculty'': The HiveQueen that controls the [[PuppeteerParasite alien parasites]] turns out to be [[spoiler:the NewTransferStudent Marybeth Louise Hutchinson]], part of the student resistance group itself. Even ''they're'' shocked by this realization, for all how their GenreSavvy nature about how horror and alien movies work has helped them survive.
* Though the ''Franchise/PiratesOfTheCaribbean'' world is [[GrayAndGrayMorality full of gray]] at the best of times, it's nevertheless a big shock to Jack Sparrow in ''[[Film/PiratesOfTheCaribbeanOnStrangerTides On Stranger Tides]]'' that his old friend and one-time flame Angelica is not only the first mate of ''Blackbeard'' but got that position by claiming to be his daughter. [[spoiler:He gets a double-dose of surprise when he assumes it's a scam to use the man to find the Fountain Of Youth, and she explains she actually is loyal to him and that she actually ''is'' his biological daughter]].
* ''Film/{{Valentine}}'': The film's final shot reveals that [[spoiler:Kate's boyfriend Adam Carr is a cover identity for Jeremy Melton, the vengeful SerialKiller picking off her friends over an offense they committed against him years ago. Also counts as LoveInterestTraitor.]]
* ''Film/DoctorStrangeInTheMultiverseOfMadness'': In order to stop the multiversal demon chasing after America Chavez from stealing her powers of multiverse travel, Strange goes to [[spoiler:Wanda for assistance, asking her to come to Kamar-Taj to help them since she's one of the strongest Avengers and a powerful magic user who helped them defeat Thanos. Wanda counters by offering to host America at her farm instead, but in making the offer she ends up [[NiceJobFixingItVillain accidentally outing herself]] as the one trying to steal America's powers, because [[INeverSaidItWasPoison she refers to America by name despite Strange never having mentioned it in their conversation.]]]]

* In ''VisualNovel/DokiDokiLiteratureClub'', well, [[MinimalistCast there aren't really characters that aren't]] the {{Player Character}}'s friends, although at first it doesn't look like there will be any villain either. [[SurpriseCreepy Then things start going horribly wrong]], and it's hinted right from the start that [[spoiler: Monika]] has some part in it. This continues to become more clear, although for a long time you can do nothing but watch in incomprehension, because that really doesn't explain what's going on. It turns out [[spoiler: she has gone quite mad, [[GoMadFromTheRevelation for extraordinary reasons]], and is only maintaining her (former?) pleasant persona as a role to hide it... but she's still ''your'' friend, if not anybody else's, because [[{{Yandere}} all she cares about is getting to be with you, no matter what she has to do to others.]]]]

* The First Stuart Gibbs ''Literature/SpySchool'' novel has the hero realizing that [[spoiler: his PluckyComicRelief CynicalMentor is TheMole]], something that becomes a LateArrivalSpoiler for the rest of the series.

* The First Stuart Gibbs ''Spy School'' novel has the hero realizing that [[spoiler: his PluckyComicRelief CynicalMentor is TheMole]], something that becomes a LateArrivalSpoiler for the rest of the series.

* The First Stuart Gibbs ‘’Spy School’’ novel has the hero realizing that [[spoiler: his PluckyComicRelief CynicalMentor is TheMole]]., something that becomes a LateArrivalSpoiler for the rest of the series.

* In ''WesternAnimation/InfinityTrain'', [[spoiler:Simon starts out as Grace's closest friend, but as book 3 progresses, his refusal to change the Apex's violent ways drives a wedge until he eventually tries to usurp and kill her.]]

** Sequel series ''WesternAnimation/TheLegendOfKorra'' has Varrick for Bolin. He did betray him and his friends, intended to use Unalaq's plan for his own selfish benefit, but Bolin still respected him and was still willing to accept his help against their real enemies. This seemed to become a more legitimate, trustworthy friendship as the series progressed however.

* In the anime of ''Manga/KenichiTheMightiestDisciple'', the final boss of Ragnarok that Kenichi faces is [[spoiler: Odin/Ryuto Asamiya, Kenichi's ForgottenChildhoodFriend.]] True to being an AuthorityEqualsAsskicking figure, it takes Kenichi a few episodes to finally take him down.

* All over the place in ''Manga/AttackOnTitan''. Eren learns that [[spoiler: Annie Leonhart, the girl that taught him how to fight, is really the Female Titan responsible for slaughtering his squad mates.]] Not long after that, he learns [[spoiler: that [[TheQuietOne meek]] Bertolt Hoover and TeamDad Reiner Braun were the Colossal Titan and Armored Titan all along. And therefore, indirectly responsible for a good majority of the death in the series.]] To say he's [[YouMonster less]] [[RoaringRampageOfRevenge than]] [[YouKilledMyFather thrilled]] is an understatement. For an extra twisting of the proverbial knife, all are presented as [[TragicVillain sympathetic]] and [[BecomingTheMask genuine]] in their attachment to the people they've betrayed.

* ''[[VideoGame/{{Onmyoji}} Onmyōji]]'': [[spoiler: '''[[NiceGirl Yaobikuni]]''', my God, [[YamatoNadeshiko Yaobikuni]]. She's been ''seriously'' nice and ''seriously'' helpful to the rest of the main quartet before the revelation that everything she does is only part of her plan to serve the [[GreaterScopeVillain Yamata-no-orochi]] hits them ''hard'']].

* After Arachnophobia's arc in ''Manga/SoulEater'', it turns out that [[spoiler:Justin Law]] had gone through the first phase of this, but afterwards... well, [[spoiler:turns out that Law worships Asura, not Shinigami-sama, is an extreme misogynist, likes to be playing HoYay with his longtime apparent enemy, and more than likely helped set up Kid to be kidnapped by the arc's BigBad {{Chessmaster}}.]] So, he subverted this while acting TheMole. He might still like Stein, though, because [[spoiler:he did retreat before injuring him]].
** As of chapter 96, [[spoiler:Chrona]] is stepping up to the role too.

* In ''Another 48 Hours'', sequel to ''Film/FortyEightHours'', Jack's fellow detective, Ben Kehoe, is revealed as a big time drug dealer. The character had been used for some exposition in the first film and it was somewhat given away by having him slick back his hair and wearing a suit in the second.

TheHero is looking for answers, beating up bikers, paying off informants and searching through the GreatBigLibraryOfEverything. His [[TrueCompanions best friend]] and [[HeterosexualLifePartners partner]] pleads with him to stop, [[CrusadingWidower it won't bring "her" back]], and it just puts him in danger. Yet still the hero persists.

Compare EvilFormerFriend, TheDogWasTheMastermind, EvilMentor, and TreacherousAdvisor. Contrast FriendlyEnemy, LivingWithTheVillain, and PoisonousFriend. [[JustForFun/IThoughtItMeant Not to be confused with]] [[DidWeJustHaveTeaWithCthulhu another type of big bad friend]]. If the hero is being chummy with the BigBad, that's GoKartingWithBowser. EvilAllAlong is for anyone who turns out to be evil, not just friends. Related to TheyWereHoldingYouBack.

* Youko's PoisonousFriend Yuka Sugimoto in ''Literature/TheTwelveKingdoms'' becomes her rival to become the Queen of Kei. [[spoiler: Though unlike others, she gets better and relinquishes her claim, returning to Hourai/Japan.]]

* An inversion occurs in ''Series/{{Battlestar Galactica|2003}}''. After [[spoiler: Saul Tigh]] is outed as a Cylon, Adama accuses him of being one of these. [[spoiler: Tigh]] himself however was more of a PoisonousFriend.