A very old trope, in which left-handedness is a signal that that someone is the Villain or TheMole, or occasionally just susceptible to the HeelFaceRevolvingDoor. The word "sinister" actually is derived from the Latin word for left-handedness, and also related to the BarSinister which is a symbol of bastardy, and thus untrustworthiness.

This is also related to EvilTwin; twins [[TruthInTelevision do often have]] opposite dominant hands, and an EvilTwin will (almost invariably) be the left-handed one.

Additionally, in older times, left-handedness was often a sign of evil or trickery because of the fact that people would shake hands with their right, grabbing each other by the wrists, in order to show that they were friendly and [[NothingUpMySleeve didn't have weapons]]. A lefty could shake with their right hand, grasping the other person's dominant hand, and attack with their weapon in their left hand while the other was defenseless. Also, during the Middle Ages, towers were built so defenders would have no problem swinging their swords down staircases while attackers would have loads of problems swinging up. However, this only applied if both were right handed; if the attacker were left-handed, the two would be evenly matched.

In many cultures, before the invention of toilet paper and forks, the right hand was used for eating, greeting etc., while the left hand was used for wiping oneself and other less savory things.

Another related trope is for a character to lose his right hand, symbolizing his loss of a moral compass. This can presage a FaceHeelTurn by the Hero. It is also common for {{Mad Scientist}}s to have a mechanical right arm. Alternatively, the left hand might become the repository of SealedEvilInACan. Compare RedRightHand.

A subtrope is TheKillerWasLeftHanded, where that trope there is actually evidence that [[ExactlyWhatItSaysOnTheTin the killer was left-handed]]. Examples of that trope should go there.

The opposite, when left-handedness is viewed favorably, is TheSouthpaw. Sometimes overlaps with LeftHandedMirror. Also see IAmNotLeftHanded.
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!!Examples:

[[foldercontrol]]

[[folder:Anime & Manga]]
* Figures prominently in ''Anime/ReadOrDie''. ''Really'' prominently - will ruin the main plot twist if you read the spoiler. [[spoiler: Nancy is left-handed and is TheMole. Then to add to that she has an EvilTwin and they are differentiated only by their dominant hand. Inverted because the right handed Nancy is the EvilTwin. As an alternative interpertation, it is not inverted because left-handed Nancy betrayed Yomiko first, and then betrayed and killed her own lover (although he had betrayed her), while right handed Nancy was at least loyal to her man, making the left handed Nancy experience a HeelFaceRevolvingDoor.]]
* Wrath of ''Anime/FullmetalAlchemist'' may or may not be left handed, but he got the right one from someone else. The same could be said of Scar, though their alignments turn in opposite directions.
* Gin from ''DetectiveConan'' is left-handed. Also, there is a case Conan solves by realizing a man had been replaced by a duplicate because the fake was left handed and the original was not.
* Higuchi in ''Manga/DeathNote'', though nobody mentions it. Light's ambidexterity probably counts as well.
* ''Manga/OnePiece'': An interesting case with the Straw Hats, as none of them are evil, but a large number of them have something of importance on their left side. Luffy has his scar underneath his left eye. Nami's tatoo is on her left arm. Zoro's earrings are on his left ear, and although ambidextrous appears to prefer his left hand. Usopp always wears his wrist band on his left hand. Sanji's left eye is always covered. Chopper's antler plate is located on his left antler. Interestingly enough, the two Strawhats that finally break this pattern,[[spoiler: Robin and Franky,]] are both introduced to the story as villains/antagonists to the Strawhats. [[spoiler: Brook]] then completely subverts it, as his one asymmetrical trait is on the right side of his face.
** Sanji also subverts this after the TimeSkip, when his PeekABangs switch eyes to cover his right one instead.
** To be fair, they ''are'' all pirates.
** Also worth noting is that when DualWielding, Zoro's favored left hand is using a supposedly [[EvilWeapon cursed sword.]]
* Inverted by Nanoha, the left-handed heroine of the ''LyricalNanoha'' series, which is full of right-handed villains. Unless you take her {{fanon}} [[BloodKnight reputation]] into consideration.
* In ''Manga/{{Naruto}}'', Sasuke realizes that the Naruto in front of he and Sakura is an impostor because his knife pouch is on his left leg, implying left-handedness, while the real Naruto is right-handed.
* Very subtle and not called into view, but all the members of [[{{Yu-gi-oh5Ds}} Z-One's team]], [[spoiler: (Placido, Lucciano, Jose, Aporia, Paradox and Antimony/Bruno)]] all wore their Duel Disks on their right arm, and hence were all left-handed.
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[[folder:Comic Books]]
* Comicbook/GreenLantern villain {{Sinestro}} wears his [[GreenLanternRing power ring]] on his left hand.
** As does Alan Scott (the Golden Age GL), inverting this trope.
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[[folder:Films -- Live-Action]]
* [[TheFaceless Keyser Soze]] in ''Film/TheUsualSuspects'' is left handed. A clue to his identity occurs early in the movie, when [[spoiler:Verbal Kint tries to light a cigarette by holding the lighter in his right hand and opening it with his [[ObfuscatingDisability cerebral palsy-afflicted left hand]], but can't do it]].
* All the Stormtroopers in ''Franchise/StarWars'' are left-handed, due to the magazines on the left side of the prop guns constantly bumping into the Stormtroopers armor. Maybe this would explain ImperialStormtrooperMarksmanshipAcademy.
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[[folder:Gamebooks]]
* Inverted (thematically at least) in the ''Literature/LoneWolf'' gamebooks: magic traditions inspired by the Forces of Light are referred to as "left-handed", while the BlackMagic of the servants of [[GodOfEvil God of Darkness]] [[BigBad Naar]] are referred to as "right-handed".
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[[folder:Literature]]
* In Literature/TheBible, Ehud, one of the judges, actually managed to assassinate a king by hiding a miniature weapon on his right hip. Thus the weapon wasn't found, and he could still use it, being left-handed.
* Arya from ''ASongOfIceAndFire''. When her dominant hand is revealed to her fencing master, he reacts favorably because fighting left-handed will reverse her stance and movements, which will help confuse her opponents. However, her left-handedness might also be ASinisterClue about her future, [[spoiler: training in a cult of assassins.]]
** Subverted with Jaime Lannister, who [[spoiler:loses his right hand just before his HeelFaceTurn, ''away from'' the dark side]].
* In the novel ''TheSterkarmHandshake'', the whole Sterkarm clan are lefties and are known for being backstabbers.
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[[folder:Live-Action TV]]
* Played for laughs in some comedy (?) show called ''Inside Scoop'': [[http://www.youtube.com/watch?v=1GEI7HKE_D4 Ban Left Marriage!]]
* In ''Series/{{V}}'', whenever a human is [[MoreThanMindControl converted to the villains' cause]], it causes a brain-dominance switch. Since ThereAreNoLefties in TV Land, this leads to left-handed human collaborators.
* In ''Series/StarTrekTheNextGeneration'', Data figures out he and Picard are trapped in a holodeck Enterprise when (the simulation of) Geordi catches a tool Data throws to him with his left hand, exposing a programming glitch Data was already aware of.
** The logo of the Borg Collective looks like a grasping left hand.
* An episode of ''Series/{{Supernatural}}'' has Sam [[SpotTheImposter realize that a shapeshifter]] was pretending to be Dean because he caught something with his left hand, as Dean's left arm was injured.
* In {{Graceland}} Briggs is left handed. This trope is ony invoked later in the first deason, with the big reveal.
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[[folder:Tabletop Games]]
* ''TabletopGame/{{Paranoia}}'': "Left-handedness is one of the ten early warning signs of Commie mutant treason!"
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[[folder:Video Games]]
* Dyne, a side-villain in ''VideoGame/FinalFantasyVII'', had his crippled LEFT arm replaced with a machine gun, and is distinctly portrayed as a serial killing lunatic. The reverse is true of Barret - even though he leads a terrorist organisation that blows up a power plant and kills hundreds of people, his RIGHT hand was the one replaced with a similar weapon. He turns out to be a nice, but misguided person who is a doting father and dedicated friend.
** Sephiroth and his remnants are also lefties.
** Kain Highwind, a party member from ''VideoGame/FinalFantasyIV'', is left handed, which is shown by having weapon and shield slots in his inventory screen reversed. No points for guessing what he does, especially with [[NameOfCain a name]] [[CainAndAbel like that]]. Though he does get better... [[HeelFaceRevolvingDoor somewhat]].
** Aside from Kain the only other left handed characters in IV were Golbez, the main villain, and Palom, who while not evil or villanious was still a bit of a brat with a bad attitude.
* In ''GodHand'', the titular artifact exists in a pair: left God Hand and right God Hand. The hero, Gene, got the right one to replace his severed arm. As for the left one, it's used by the [[TheDragon Dragon]] Azel (who is the most evil in the group of villains).
* In ''VideoGame/SuperSmashBros'', the Master Hand is a giant, floating, apparently benign right hand who created the world that the characters find themselves in, and lives to be the ultimate challenge for heroes. The idea is that he is the hand of the child making the trophies fight, just like a kid in his room playing with action figures. His EvilTwin is the Crazy Hand, the left hand of the pair, who laughs maniacally upon his entrance and whose attacks and general movements are both bizarre and incredibly erratic. Whereas Master Hand is said to be a benign force and to represent the creative nature of a child, Crazy Hand is a destroyer, and supposedly represents that same child's more sadistic qualities. In the end, Master Hand doesn't look particularly saintly himself with his equally EvilLaugh, and [[BigBadDuumvirate both hands]] still serve as the final bosses of the modes where they appear, so the implications of good versus evil between them are [[DownplayedTrope downplayed]].
* An odd example occurs in the online game ''ImprobableIsland'', where one of the monsters you can encounter is called "Sinister Dexter", an AffectionateParody of, well, ''Series/{{Dexter}}''. His moves are all based on being left-handed. [[RealityIsOutToLunch It's that kind of game]].
* The official art for ''Castlevania: Symphony of the Night'' depicts [[spoiler:cursed-by-Dracula]] Richter Belmont as a lefty; he is right-handed in the prior depictions of him. Hint hint much.
* The two models of the [[VideoGame/PokemonColosseum portable Snag Machine]] are depicted as being worn on the left arm. Neither of their wielders are particularly nasty ([[AntiHero though one moreso than the other]]), but the folks behind inventing the device are the epitome of evil in the Pokeverse.
** As a comparison, in ''[[VideoGame/PokemonXDGaleOfDarkness XD]]'', Michael always makes a regular catch (at the Poke Spots, given that's where wild Pokemon appear from time to time) or calls out a Pokemon with his right hand. He only uses his left when he needs to make a Snag.
* Inverted in VideoGame/TalesOfTheAbyss, where TheHero is left-handed, [[spoiler:while his EvilTwin is right-handed, or at least favours his right hand in combat, allowing the pair to milk FearfulSymmetry for all its worth.]]
* Subverted in ''VisualNovel/HatofulBoyfriend''. The ObviouslyEvil Dr. Shuu uses his left [[FeatherFingers wing]] for everything... because his right wing was injured in the past.
* Interestingly, the Wii version of ''VideoGame/TheLegendOfZeldaTwilightPrincess'' had [[TheHero Link]], who is traditionally TheSouthpaw. Because of controls, Link had to be turned right-handed, but the deadline of the game was getting close, so they decided to simply mirror the whole game, thus turning most characters left-handed and making [[BigBad Ganondorf]] this trope.
* In the ''VideoGame/SoulSeries'', Siegfried Schtauffen and thus his SuperpoweredEvilSide, Nightmare, are ambidextrous. However, while Siegfried prefers to wield his sword in his right hand, Nightmare prefers to wield it in his left hand.
** The new Nightmare in ''Soulcalibur 5'' is left-handed. It's assumed that his new host, Graf Dumas, is actually [[spoiler:Raphael Sorel, the only left-handed fighter besides the new Nightmare]].
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[[folder:Webcomics]]
* ''Casey and Andy'': Satan is left-handed.
* ''Narbonic'': Caliban is left-handed.
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[[folder:WesternAnimation]]
* In one "Treehouse of Horror" episode of ''WesternAnimation/TheSimpsons'', left-handed Bart turns out to be the evil twin of Hugo Simpson. Bart's left-handedness is never brought up in the episode though.
** There's no indication as to whether either Bart or Hugo is left- or right-handed; however, Bart was the left-sided (or Sinister) twin.
* Francine from ''WesternAnimation/AmericanDad'' was raised to think lefties were evil.
* In one episode of ''WesternAnimation/TheBatman'', Mirror Master creates evil duplicates of Batman, Robin, and Flash. Batman quickly notes that the duplicates are left-handed.
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!!Examples of the related tropes:

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[[folder:Anime and Manga]]
* The left hand of the titular character of ''HellTeacherNube'' is actually a sealed Oni, Baki, which replaces the left hand he lost fighting said Oni. Most of the time, it looks like his regular hand wearing a black leather glove; when his students are threatened by spectral horrors, he will reveal it as a monstrously large, dark red hand with visible tendons and black claws. However, he constantly seeks a way to seal it permanently, as only the influence of his childhood teacher prevents the Oni from taking over his entire body.
* The lead characters of ''Manga/{{Parasyte}}'' are a young man named Shinichi and the alien parasite that has possessed/replaced his right hand. Their relationship is one of the main foci of the series, especially re: Shinichi losing part of his humanity. As early as the first volume, the LoveInterest intuits there's something weird about his right hand and switches around him to hold his left instead.
** The original English translation was flipped and 'Migi' was named 'Lefty' instead.
* Edward Elric of ''Manga/FullmetalAlchemist'' lost his right arm and his brother lost his entire body performing forbidden alchemy, which put him on a self-imposed RedemptionQuest to restore his brother's real body. At the end of the story, [[spoiler: he has his right arm and his brother back, but Edward had to give up his ability to perform alchemy.]]
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[[folder:Comic Books]]
* [[{{Superman}} Lex Luthor]] also had a mechanical right hand for a while; he lost the original to Kryptonite poisoning. Naturally, he took Rotwang's role in the {{Elseworld}} ''Superman's Metropolis''.
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[[folder:Film]]
* Reverend Harry Powell from ''Film/TheNightOfTheHunter'' 1955. The fingers on his right hand are [[KnuckleTattoos tattooed with the word L O V E]], while the left hand is tattooed H A T E. His CatchPhrase? "Do you want to hear the story of left-hand and right-hand?"
* In ''Franchise/StarWars Episode II: Film/AttackOfTheClones'' Anakin loses his right arm- symbolism of a move towards the Dark Side? Luke then loses his right hand in the same way- right before TheReveal that LukeIAmYourFather, and in ''Return of the Jedi'' Luke breaks free from his FreakOut after he cuts off his father's right hand and realizes that both of them have mechanical right hands.
* Rotwang ''Film/{{Metropolis}}'' 1926, here we have the subtrope with the MadScientist whose right hand is mechanical- also seen in Webcomic/GirlGenius with Professor Mongfish.
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[[folder:Literature]]
* In the books, [[TheSilenceOfTheLambs Hannibal Lecter]] had six fingers on his left hand.
* Inverted in ASongOfIceAndFire. When [[spoiler: Jaime Lannister]] loses his right hand, his moral compass actually starts working better. This is mostly because without his sword-hand, he's forced to think things through, when before he could just hack his way through any obstacle.
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[[folder:Video Games]]
* In ''VideoGame/TheWorldEndsWithYou'' Sho Minamimoto has a black left hand.
* The main villain of ''VideoGame/FinalFantasyIV'', Golbez, is left-handed. However, you only learn this when [[spoiler:he's freed from brainwashing (done by the ''real'' villain) and becomes a protagonist in the sequel]]. He wields weapons in his left and shields in his right. Similarly, [[spoiler:Kain]] is left-handed, and ends up brainwashed to fight for the villain.
* Notably inverted with a lot of the characters Shigeru Miyamoto creates. [[Franchise/SuperMarioBros Mario]] and [[Franchise/TheLegendOfZelda Link]] are both left-handed (though the default latter has changed with the sword swinging of the Wii titles), and Miyamoto himself is ambidextrous, preferring his left hand.
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