This was the whole point of the series 2: The evil one is the first to discover he has a twin, and frames him for his own crimes.
3rd Rock from the Sun had Dick temporarily replaced as high commander by another alien who takes on the same human form and identity. This replacement (called simply "New Dick") is not only an evil megalomaniac, but he is also "extremely unpleasant." Even more than the original.
A recurring version, although not a twin (not even related), was Galina, a patient in a Minsk mental institution and prone to violent outbursts. Russian government officials (presumably, with permission from the Belarus authorities) take her to a secret location and turn her into a look-alike for the scientist Olga. The goal is to infiltrate the Backstep project and steal the secret of the Sphere for the Russian version of the project. After Galina is cleaned up a bit, she becomes a dead ringer for Olga, although their personalities are very different, and people notice "Olga" acting strangely. Namely Parker, who spends many episodes unsuccessfully trying to get Olga into bed suddenly finds her trying to jump him.
A more conventional version was also done in this series. In a season 1 two-parter, Parker is accidentally duplicated by the Sphere during a Backstep hurriedly undertaken during an incomplete tech upgrade. At first it seems as though they're going to clash with each other because they're both the same alpha-male personality (as with the duplication of Crichton on Farscape), but it quickly develops that the duplicate Parker is an ultranationalist sociopathic asshat for some reason.
Alias gives us this trope via Project Helix. Two major characters (Francie and later Sydney) had evil versions, and several minor characters as well.
Of course we can't forget Arrested Development featuring the Evil Twin as a major plot point where George consistently traded places with his luxuriously hirsute good twin Oscar. Dot com.
One such incident reveals that multiple people arrested by the police try to play the "You've got the wrong twin" card, with no success.
In Season 5 of Arrow, Felicity actually namedrops this trope while trying to figure out Black Siren's true identity.
Kosh and Ulkesh (Kosh II) in Babylon 5 sort of had this dynamic, although as far as we know they aren't siblings.
In the 2002 revival of The Basil Brush Show there's Basil's cousin Mortimer who is a criminal mastermind.
In Batman (1966) TV series, one episode has the musical virtuoso Chandell, who is being blackmailed by his criminal twin brother Harry. (Both brothers were played by Special Guest Liberace.)
Played with in Battlestar Galactica (2003). Boomer and Athena are a pair of Sharons/Eights who are set up as equivalents. Initially, Boomer seems to be more moral and Athena inclines towards the Dark Side, but both sway in both directions in the course of the series. By the end, Boomer has spent more time doing bad things (some of them very bad) while Athena is the nobler twin.
The Evil Twin is a common trope for Brazilian soap operas to this day.
Discussed in Brooklyn Nine-Nine. Cloudcuckoolander Jake declares that in every set of twins, one of them is always evil, and applies this logic to the Jeffords twins, Cagney and Lacey. Their father Terry irritably points out the girls are four. For some reason, Jake thinks the evil one is "obviously" Cagney. In reality, both girls are sweet and fairly well-behaved for the most part.
Vampire Willow and Vampire Xander in "The Wish". Vampire Willow returned in "Doppelgangland" and actually met her good counterpart, making her a better example.
The trope is later subverted in "The Replacement". A demon's spell, meant for Buffy, hits Xander instead, splitting him in two. He spends the rest of the episode tracking his twin while the twin interacts with his friends and makes various changes to his life. At the end it's revealed that the blast doesn't split you into Good/Bad, but rather into Strong/Weak. The Xander that the audience thought was the "Good" Xander was actually the "Weak" one and the "Strong" one wasn't doing anything harmful to his life and was actually improving it. The demon's plot hinged on the fact that if one of the twins was killed, both would die. He'd planned to split Buffy into a Slayer powered version and a valley girl version, then kill the latter. In this case, the special effects crew had an easy time getting both Xanders in the same shot. Xander's twin was played by Nicholas Brendon's identical twin brother, Kelly Donovan (who may or may not be evil).
Averted in Castle. The murder victim (Zalman) had a twin brother (Edmund), who wore eyeglasses and turned up mysteriously while Castle and Beckett were searching the victim's secret magic workshop. Castle immediately lampshades this trope and speculates that Edmund was the victim and Zalman murdered him to assume his happy family life and prosperous, stable job as an accountant, while inheriting his own magic shop plus insurance money. Played straight; Lanie double checks the fingerprints and immediately rules Castle's theory out. While the twins were very different, both were good guys who lacked stage presence.
Paige had an evil past incarnation travel to the present who looks just like her.
Community Season 3, Episode 4, "Remedial Chaos Theory", features seven alternate timelines. The Abed in Timeline 1 recognises it as the darkest timeline (Pierce is dead, Annie's crazy, Jeff lost an arm, Shirley's a drunk, Troy lost his larynx and Britta dyed a strip of her hair blue) and suggests the group embrace their role as evil versions of the Main Timeline group.
In the fourth season episode "The Angel Maker", an executed serial killer appears to be back, complete with possible DNA evidence. Reid floats the idea of 'evil twin, eviler twin', but no one else buys it. And they're right, too.
The episode "The Inspiration" ends with the revelation that the man they arrested wasn't behaving properly because he was the actual unsub's long-lost brother. Part two, "The Inspired", reveals that it's more a case of crazy twin, evil twin. While neither brother is an especially good guy, one's crimes are motivated by his mental illness while the other is simply a sociopath.
On CSI the Gig Harbor Killer, a serial killer from Seattle who kidnapped DB's granddaughter, is revealed to have a highly successful long-lost twin (they were adopted into different families). Successful-twin sincerely believes his brother is innocent and claims he didn't know of him until he was caught but having met them both DB's pretty sure they were already partners back in Seattle.
In an unusual example, Dark Angel introduces the evil one first. Jensen Ackles's first character Ben is a disturbed Serial Killer; his identical twin brother Alec, introduced a season after Ben's death, is a sane Loveable Rogue who becomes one of the main heroes of the series... even if he does have his rough patches. Borderline case; leaving aside that Ben is arguably more insane than evil, unlike most examples they never co-exist on the show, although Alec does get arrested for one of Ben's murders in the episode "Hello, Goodbye".
In Dark Oracle the major antagonists, Blaze and Violet fall somewhere between this and Evil Counterpart, being denizens of the Dark World physically identical to heroes Lance and Cally. Evil Sage (Season 2, Episode 3, "Through A Glass Darkly") on the other hand, plays this absolutely straight, being the Dark World twin of Lance's girlfriend, Sage, and her complete opposite in terms of personality. Whereas real-world Sage is a geekily-cute girl, with low self-esteem and very odd taste in—well pretty much everything—her comic book counterpart is a vindictive bitch with creepy heterochromia, evil tattoos, and a plethora of Kick the Dog moments. She's hyper-aggressive to Sage's shyness, enjoys playing mind games with Lance, and looses a poisonous snake on a pair of girls who defaced her locker. It takes a near-death experience to bring the real Sage back.
In the Fox TV movie Dark Reflection (aka, Natural Selection), C. Thomas Howell plays a dual role. In one role, he is a successful computer programmer named Ben with a great house and an awesome sports car but is neglectful of his wife and son. In the other role, he is Adam, a clone of Ben who has been running around the country killing his other clones and taking over their lives. (There were seven clones altogether.) Well, Ben is last on the list. So, Adam gets a job at Ben's company, charms the wife and kid, and infiltrates Ben's life to learn all the little details he will need to accomplish his evil plan. Along the way, Adam kills a private detective, who has figured it all out, and Ben's mother, who is the only one who know that Ben has a clone. He also has sex with Ben's wife, who can't tell the difference. In the climax, Ben and Adam fight on the roof and one kills the other. At the end, we find out that Adam survived, and that he's actually a better father to Ben's son and a better husband to his wife. Neither of them know they're now living with a murderous clone who has killed the real Ben and several others.
A well-known American soap opera example is Andre DiMera from Days of Our Lives. Andre was given plastic surgery to make him look like his cousin Tony at the contrivance of the man Tony grew up believing was his father, crime lord/practical supervillain Stefano DiMera. At Stefano's behest and while Tony was kept secretly imprisoned, Andre while impersonating Tony became a serial killer just to frame an enemy of Stefano's, although Stefano ended up betraying him once Andre's killing spree included Stefano's own daughter (although that didn't stop Stefano many years later getting Andre to pretend to be Tony again!).
In "The Chase", the Daleks create an android First Doctor as part of their plan to kill the TARDIS crew. Slightly spoiled by the fact the actor doesn't look entirely like William Hartnell.
Evil dictator Salamander from "The Enemy of the World" is an evil twin for the Second Doctor. However, since the Doctor has a lot of specialized knowledge, including the operation of the TARDIS, he was easy to uncover when he tried to impersonate him.
Happens again in "The Android Invasion" — android duplicates are created of the Doctor and many other characters.
The Dukes of Hazzard: Two instances, both involving the series' two main villains (one each per episode):
The episode "Baa Baa White Sheep" introduces Boss Hogg's good twin, Abraham Lincoln Hogg (Sorrell Booke in a dual role), who is everything his brother isn't; A.L. Hogg is kind, charitable, and decent. He wears a priest's black outfit and a black stovepipe hat, and drives a black car, in contrast to his brother's white duds and white vehicle. The twins' parents must have foreseen how their sons would have turned out; astute viewers will recognize that the twins are named after Abraham Lincoln and Jefferson Davis, the Presidents of the Union and the Confederacy, respectively, during the American Civil War.
In "Too Many Roscoes," the real Roscoe is kidnapped by a band of bank robbers while the ringleader — an impersonator named Woody (James Best in a dual role) — takes to the streets assuming Roscoe's identity... all to help his two criminal associates gain control of an armored truck delivering a $1 million shipment to Hazzard Bank. (Incidentally, the main characters fail to call Woody on his fake identity when "Roscoe" bungles simple facts about his friends but remembers facts about the expected bank shipment in exact detail.)
The TV movie Echo had Jack Wagner play an evil twin brother who kidnapped the main character and move into his life, killing his remaining relatives in the process, until at the end when the character's girlfriend confronts them both in the abandoned building, she doesn't know which one is the evil twin and ends up shooting one of them, with the audience also left wondering which one was killed.
Subverted in one episode of Elementary. The twins in question are fraternal twins, not identical, so there wasn't any impersonation of the good twin. Some aspects of this trope are played with, namely framing/trying to kill off the good twin.
Parodied in one episode of Even Stevens, where Louis meets a lookalike with a similar name from a different school, who starts playing pranks on everyone and gets him blamed for it. Louis isn't really upset about that, but rather about the fact that the pranks being pulled are so amateurish and sloppy as to ruin his reputation as a prankster.
Fantasy Island once revealed that Mr. Roarke and Tattoo had their own evil (non-identical) twins, who wore black suits with white ties, and had British Accents. Perhaps ironically, the 1998 reboot of Fantasy Island starred British actor Malcolm McDowell, complete with a black suit, as Mr. Roarke. In a separate episode of the original series called "Look Alikes", a guest (Ken Berry) wishes to meet and exchange places with his (non related) twin (Ken Berry) who he has never met, and who of course turns out to be wanted by some bad guys.
Subverted in Farscape's third season, in which a second John Crichton is created... yet is absolutely the same as the first Crichton. However, it's essentially played straight in the episode "My Three Crichtons", which features John being triplicated into himself, a caveman, and a future-brain-man-thing. Strangely enough, only that last one is actually evil.
In Father Dowling Mysteries, the eponymous priest had an evil twin who was a criminal and would pop in and cause trouble.
Phoebe's twin sister, Ursula, is by all accounts a bad person: she's an awful waitress, nearly cons a man into marrying her, sold Phoebe's birth certificate to a stranger, becomes a porn star using Phoebe's name, and generally has no affection for Phoebe. She also didn't tell Phoebe that their mother had left a suicide note, and tried to improvise one on the spot when Phoebe asked to see it.
Parodied in another episode, when Joey was dating someone who honestly believed he was the character he played on TV, Dr. Drake Ramore. When she sees him in person while the show plays on the TV in the background, she becomes confused. Joey tells her the truth but she doesn't understand, so Ross tells her that he is actually Hans Ramore, Drake's evil twin.
General Hospital once had an interesting take on this. There was once a character named Grant Putnam who was revealed to The Mole for the Soviet Union. The Power of Love redeems him and after helping to dispense with his comrades, continues his life. Eventually the Not Quite Dead real Grant Putnam recovers from amnesia. At first it seems he's evil due to the trauma of nearly dying and spending years in an asylum, but it's revealed that he was Evil All Along and had originally murdered his brother in order to have his brother's fiancée, who's now married to the Russian.
In Chinese TV series 神医大道 (English title: "God Of Medicine") a maid-servant is magically transformed into the princess's evil twin. Then the princess is transformed into a duplicate of the maid, becoming her good twin. It's almost a Grand Theft Me, except that the changes happen separately.
Alton Brown's evil twin, B.A., is a recurring character on Good Eats, usually to provide contrast as Alton and B.A. make sweet and spicy varieties of the same dish. Despite the fact that B.A. is "evil", and has been in and out of jail numerous times, Alton and B.A. seem to get along relatively well. Of course, this might be because B.A.'s also The Voiceless, and Alton provides the running commentary on anything B.A. makes.
Gotham: Jerome Valeska is a rather disturbed man who killed his own mom without any remorse and treating the suffering of others as a joke. On the other hand, his twin Jeremiah appears to be a reclusive, yet relatively harmless genius. And then it's completely flipped on its head, as Jeremiah hints that he may have been Evil All Along. Oh yeah, and it's Jeremiah who ultimately becomes the infamous Clown Prince of Crime.
Gunsmoke: In one episode, Festus is jailed on charges of murder and robbery... only someone who looked just like him was the actual criminal.
Hannah Montana has this with Miley's cousin Luann, who looks like her, does bad things to her, and even tricks other people at a Halloween party that she's the real Hannah just to ruin Miley's alter ego's reputation. Luckily, she only showed up in one episode.
There's also Luann's dad, who is Robbie Ray's identical twin brother. He isn't actually evil himself, but seeing two Robbies side by side does freak out the snooty neighbor.
Heroes has begun this trope as an "evil" character Sylar gained shapeshifting abilities and has begun taking on the roles of a "good" character Nathan Petrelli. (Though their good and evil roles seem to change episode by episode.)
Himmelsdalen: Siri turns out to be a very dangerous, manipulative sociopath who murdered a mother and daughter, then switches places with Helena, her normal twin, so she can escape a mental institution. Even as a child, Siri stole her toys out of spite, hiding them from Helena, and killed her dog (to Helena's only much later realization).
One episode of Homicide: Life on the Street featured a pair of twins, one of whom was a serial killer who was dragging his brother along on his murder spree. However, the evil brother genuinely cares for the good one and ultimately turns himself in when his brother is arrested after being mistaken for him.
Each of the main characters in How I Met Your Mother has a doppelganger. Lily's duplicate Jasmine is a clear Evil Twin who robs Barney, Ted, and Robin. However, Barney's doppelganger, Dr John Stangel, is a mature and well-respected fertility doctor who is visibly unamused by his duplicate's antics, making Barney the Evil Twin.
iCarly in the episode iTwins. Essentially, the main character Sam is the evil twin, and Melanie is the good twin.
This is continued in the Sam & Cat episode "#Twinfection", but somewhat inverted. As a trick, Sam convinces Cat that she had the title infection and had an evil twin. Sam tells Melanie to be ten times as bad as Sam usually is.
In I Dream of Jeannie. Jeannie's sister (also named Jeannie, also played by Barbara Eden, but with a brunette wig) was not truly her twin, but could easily pass for her sister and was clearly evil, trying many times to steal Tony for herself. Jeannie's sister wore a green version of Jeannie's pink harem girl outfit, but with a skirt rather than pantaloons.
A two-part episode of The Incredible Hulk (1977) introduced viewers to another Hulk, created by a similar process to the one that transformed David Banner — but even more wild than the one we know, and actively malevolent and murderous.
Frequently discussed by the characters and the narrator as a well-worn telenovela trope. Rogelio considers it an old cliché.
Petra is revealed to have a twin sister, Anezka. While she posits as the nicer, more eccentric, mousier sister to the cold and unfriendly Petra, she's later revealed to be scheming to get Petra out of the picture and take over her life.
Kamen Rider Fourze has a literal version with the GeminiZodiarts. When the Transformation Trinket is used, it produces an Evil Twin of the user, which does its best to strengthen its own existence while weakening the original's. As this happens, the stronger one resembles a normal human while the weaker becomes more "fake" (such as their face becoming a solid white mask). After a set amount of time, the stronger side becomes permanent and the weaker side fades out of existence completely. Unfortunately for our heroes, this is happening to Kamen Rider Club member Yuuki.
Kamen Rider Ghost also has one in the form of a doppelganger of Makoto Fukami/Kamen Rider Specter. The doppelganger wears the Ganma's military uniform and sports Ax-Crazypsychotic grins to distinguish himself from the real one. Each time the doppelganger is curbstomped by the real Makoto, the latter experiences pain in the aftermath of a fight. By the time the series reaches its climax, this trope is taken up a notch when Doppelganger!Makoto gains his own Deep Specter Eyecon and starts wearing the real Makoto's leather outfit to further fool his friends, and eventually sides with his real self in earnest.
Knight Rider, a show with only three regular human characters, featured four evil twins; KITT, whose prototype KARR appeared in "Trust Doesn't Rust" and "KITT vs KARR", Michael, whose surgically reconstructed face was revealed to be based on the long-lost Garthe in "Goliath" and "Goliath Returns", Bonnie has an imposter wearing a Latex Perfection disguise in "Killer KITT", and Devon, who had a surgically reconstructed duplicate in "Knight of the Juggernaut". A script commissioned but never produced was to introduce yet another "evil twin", Devon's unscrupulous, though not actually evil, twin brother.
The Law & Order episode "Brother's Keeper." The good twin is a mild-mannered citizen, while the bad one is a member of the Irish mob. In a twist, it's revealed that the "good" twin committed murder, and the "evil" twin killed a witness to that murder, then took the rap himself, knowing that he'd get killed in prison. Which he did.
In the Law & Order: Special Victims Unit episode "Double Strands", the rapist and his wrongfully accused twin brother are played by T.R. Knight. ADA Novak understandably flips out when she's told this, citing this as the definition of reasonable doubt. The evil twin follows his blissfully ignorant and successful brother (their mother gave them up for adoption separately) around the country and rapes women, when he knows his brother doesn't have an alibi. He slips up when his brother alters his schedule one day, and then leaves a fingerprint on a screwdriver (identical twins have the same DNA but different fingerprints).
Lexx, presumably due to casting limitations, featured an endless supply of twins, some good, some evil. In a bit of Lampshade Hanging, the characters theorized that there were only a finite number of archetypes for human appearances.
In Lidsville the villain Hoodoo had a good twin, Bruce, the White Sheep of the family.
Lois & Clark had Lois' evil twin, who was a clone. And Superman's misguided-and-sees-Lex-as-his-father twin, who was also a clone.
Malcolm in the Middle had a hilarious inversion. Dewey is finding people who are just giving him money for no reason. At first he doesn't question it, but Reese finds out that there's another kid who looks just like Dewey. He then surmises that for every person there is an evil opposite. When Dewey is worried that he's met his evil twin, Reese points out the kid is virtually a saint and that Dewey is the Evil Twin. Reese then recruits Dewey to do a lot of bad things and get the other kid blamed, but by the end of the episode, Dewey tells the other kid's older brother on what's going on and gets Reese beaten up.
The Man Show features the beautiful Costello twins, Julie and Shawnie amongst their "Juggy Dance Squad". According to the behind the scenes "Know Your Juggies" featurette Julie is the good twin whilst Shawnie is in fact pure evil.
In the Masters of Horror episode "Imprint", the disfigured prostitute reveals at the end that she has a twin "sister", a mutated abomination attached to her head as a result of her parents' inbreeding (they were brother and sister). The mutant forced her sister to do evil things like steal a valuable ring and set up another prostitute to be tortured for it.
The second season Mighty Morphin' Power Rangers episode "The Return Of The Green Ranger" gives us a clone of Tommy, repowered with the Green Ranger powers and evil. He easily hands the real Tommy his rear and the resummoned Dragonzord easily trounces the Thunder Megazord. Thankfully, defeating the wizard that created him frees him from being evil, and he and Tommy go back to the past and allow the clone to live there in peace.
In the finale of Season Two, "Blue Ranger Gone Bad," Billy gets his own evil twin.
The renewed series of Mission: Impossible had its own unique take on this, thanks to Latex Perfection. An IMF agent who'd gone insane after a head injury was carrying out murders while disguised as Jim Phelps. Naturally he had all the training and skills that Phelps had, making him an Evil Twin in all but name. Well, that explains the first movie.
Robert Robertson for his triplet Cameron, whom he impersonated in a plan to kill his father, sister, and anyone else who got in his way.
Andrea Somers was originally introduced as an Identical Stranger for Dione Bliss, whom she impersonated in hopes of getting her parents' inheritance. They were retconned to be twins Separated at Birth two years later.
Stick Stickly, the stick puppet host of Nickelodeon's Nick in the Afternoon, had a diabolical lookalike, Evil Stick, who once tried to take over the summer programming block.
Gwen, Fiona Brake’s identical sister in Night and Day, isn't outright evil; but she's certainly an antagonist, who swiftly makes a beeline for Fiona’s husband Mike.
One Life to Live had an aversion with Mortimer Bern, the good twin to crime lord Carlo Hesser. However, he didn't stay good once Carlo's lover Alex propped him up to take over Carlo's criminal empire (although he did get better)...
The ninth clone introduced (counting three killed before the series starts), Helena, was raised by a group of religious extremists to kill off the other clones. At first, the other characters just assume, as the audience is meant to, that she's just another clone; but she's ultimately revealed to literally be Sarah's twin sister. It's ultimately subverted, however. Helena may be murderous, but she's not evil — she's just an abused young woman who's been taught some very bad morals. Over time, she goes through a Heel–Face Turn.
Rachel — clone number ten — may be a very dark grey as opposed to pure black, but also fits into this trope.
Out of This World (1987): Evie splits herself in order to attend a party while also writing a speech about the evils of school uniforms (specifically, bright yellow dresses with blue baseball caps, and breeches for the boys). Unsurprisingly, the process results in a serious Evie and a reckless Evie. The serious Evie is portrayed as the "real" one, at least until Serious-Evie tries to give her speech and discovers that she's now in favor of the dress code. Troy attributes their eventual recombination to The Power of Love, which is kind of Squickworthy if you think too hard about it.
Planet Ajay's Big Bad, Badjay, is the troublemaking twin brother of the show's main character, Ajay.
Popular had Bobbi and Jessie Glass working at Kennedy High (as well as their brother Rock). Bobbi and Rock were notoriously mean and unpleasant, while Jessie the nurse seemed a bit nicer, comparatively speaking. And yet, in the first season finale, Jessie plotted to kill her twin and frame all of Bobbi's sophomore biology class for the murder. Who's the mean one now?
Pretty Little Liars outright abused this along with Identical Stranger, with the reveals of Uber — A Mary Drake, Spencer's mother and killer of her own twin sister, Jessica Drake and AD Spencer's twin sister, Alex Drake.
Discussed on QI: Stephen Fry asks how to determine which of identical twins committed a crime if you have eyewitness accounts, fingerprints, and DNA evidencenote The answer is the fingerprints, which though very similar are not identical. Jimmy Carr responds "they're twins — it's the evil one!"
The 1970s science fiction parody series Quark also hit this trope in an episode called "The Good, The Bad, and the Ficus". Spock-like Ficus, being a plant, had no morality to invert when the crew of the ship was duplicated.
An episode of the usually extremely down-to-earth Route 66, "I'm Here to Kill a King", features an assassin who looks exactly like lead character Tod and is played by Martin Milner.
Every member of the Spellman family is one of a set of twins, and one of each set is always evil. In Sabrina's case, her twin is Katrina. Naturally, Sabrina is the good one, and the family has a Secret Test of Character for discovering which is which: after making a seemingly final judgement based on their past good and evil deeds, both sisters are brought to a volcano, where the emcee tells the good one to cast the evil one into it, knowing only the evil one would actually do it; Katrina fails miserably by doing this without hesitation. The Other Realm even has a prison specifically for witches like this (in the "Twin Cities"), although Katrina escapes from it in one episode and in another, is able to strike at Sabrina while still there.
Aunt Zelda's evil twin is worse. Jezebelda claims to have created the Bubonic Plague; but while clearly wicked, she isn't as smart as Katrina.
"Frankenstein, Tonto, and Tarzan" sketch, Frankenstein is kidnapped and replaced by his evil brother. The big joke of that was Frankenstein was played by Phil Hartman and was inarticulate while his evil twin was played by Mel Gibson could speak proper English and Tonto and Tarzan still couldn't tell them apart.
This trope is parodied in another Saturday Night Live skit one which is titled "Jay's Evil Twin," in it... Leno uses a fake moustache to determine if his date (Joan Cusack) will put out — his evil twin Wade.
Jay's Evil Twin: What's the matter, baby? Still got your clothes on? [releases an evil laugh as he shakes the beer can] Kate: Oh, uh.. I don't want that beer.. I.. no, thank you, Jay. Jay's Evil Twin: [releases an evil laugh] Wet t-shirt contest, baby? [pulls the tab on the beer can, gushing beer all over Kate's clothes] Kate: Why! You're not Jay! You're Wade, his evil twin! Jay's Evil Twin: [releases an evil laugh] Jay — that little weasel! That sniveling druid! What kind of a man would read Our Bodies Ourselves? I've got my own version of that book, baby — it's called Your Body Myself![releases an evil laugh] Kate: Ohhh, that's evil! You're an evil, evil man! [runs quickly out of the apartment] Jay Leno: [releases an evil laugh, as he peels the fake moustache off his upper lip] You know.. I had a hunch that dame wasn't going to come across on the first date. You know, this evil twin thing works every time — I could have blown three hours and who knows how much dough on that girl. But, anyway.. [checks his watch] My God, it's still early... I can still go to Hef's place, maybe meet somebody else there. See you later. [releases evil laugh as he exits the apartment]
The soap opera parody "The Young and The Youthful" plays with this trope by having Alec Baldwin portray both the handsome and wealthy Pierce Talbott and his mentally challenged evil twin Petey, who takes his place. Much of the humor comes from the other characters' apparent inability to immediately recognize that Petey has taken Pierce's place.
Delaney: Pierce Talbott has been acting strange lately. He cancelled all his meetings, then he locked himself in his office and watched cartoons all day long. Shane: That doesn't sound like Pierce Talbott... Delaney: Watched and sang along... Shane: That doesn't sound like Pierce Talbott at all...
The Secret World of Alex Mack has Alex accidentally come into contact with a compound called "GC Divide" which splits her puddle form into two people with distinct personalities, one being the regular Alex, and the other being her repressed bad-girl side that tries to eliminate her good half on two separate occasions, as well as just being unpleasant to everyone around her.
The Channel Four comedy-drama Shameless (UK) had the Good Twin variety: homophobic villain Paddy Maguire turns out to have a homosexual and non-villainous twin brother.
Sherlock uses this as a Discussed Trope in "The Abominable Bride", in which it's Played for Laughs. Said bride has apparently come back to life to murder someone after witnesses saw her blowing her own brains out. Watson suggests that she might have a twin sister who committed the murder. This is dismissed by Sherlock with irritation; her only relative was a brother who died years before. Watson then suggests that she might have a secret twin!
Watson: Hmm, you know? A twin that nobody knows about? This whole thing could have been planned. Holmes: Since the moment of conception? How breathtakingly prescient of her!It is never twins, Watson.
Lord John Roxton gets one in one episode of Sir Arthur Conan Doyle's The Lost World after he is cursed for disturbing a graveyard's peace. The protector takes the ruthless and violent part — basically the hunter part — out of him and gives it a life of its own. Evil!Roxton tries to kill the good one, using Marguerite as bait. It ends in a Mirror Match.
The series featured numerous evil twins, including one case where there is a No Ending in which one of the regulars may have been permanently replaced by his twin.
For a while, there was an online game about the series involving the Player Character as a new slider who has to figure out which of the four other members (Quinn, Colin, Maggie, and Rembrandt) has been replaced by an Evil Twin before they have to slide. Basically, it's a trivia game where you ask each character questions about past adventures (i.e. episodes) and try to spot inconsistencies. The game is not randomized, so the impostor is always Colin. The inconsistency involves the episode where Colin and Maggie were drugged to live a happy life together. The impostor claims that he hated every minute of it. In fact, the real Colin, being pumped full of drugs, loved it.
Bizarro Clark, of course, whose distinguishing characteristic was that he'd wear the opposite jacket/shirt combo (red jacket/blue shirt if Clark's got a blue jacket/red shirt, etc.) and no one noticed. Also, in the episode "Onyx", Lex Luthor is split into a Good Lex and a Crazy/Evil Lex.
In one subplot of Soap, Burt is kidnapped by space aliens, one of who is transformed into an exact duplicate of him, who's not so much evil as horny for Burt's wife. Burt gets the aliens to return him to Earth, leading to this touching yet funny scene of Richard Mulligan acting with himself.
So Weird: "Pen Pal": Random supernatural occurrences cause Annie to come face-to-face with a parallel universe counterpart who has fallen in with a bad crowd, and thereby turned "evil." (Well, goth and rebellious. This being a Disney show, that's about as evil as a character could get.)
The final Space Cases episode to air, "Trouble With Doubles":
Commander Goddard: We have an Evil Twin situation.
Star Cops: In "A Double Life", Albi is an evil clone of the famous pianist James Bannerman.
Samantha Carter had an evil replicator version of herself, Replicator Carter (Replicarter) who nearly takes over the entire galaxy.
Starsky & Hutch each have one in "Starsky And Hutch Are Guilty". These evil twins are actually two look-alikes disguised as the title characters, pinning crimes on the original duo under orders of a corrupt attorney.
As well as having a double in the Mirror Universe, Kirk also had an android duplicate ("What Are Little Girls Made Of?") and an evil double created by a transporter accident ("The Enemy Within"). The transporter double was an interesting case, as it actually split Kirk into a "Good" and "Evil" version of himself. The good Kirk lacked the strength of purpose to command, while the evil Kirk, while violent, ultimately lacked the moral courage to face the situation. While hating each other, both finally realize they need each other to survive.
William Riker has one, thanks to a transporter malfunction, who at first is just missing some social niceties after being stranded on a planet alone for the better part of a decade.
And then "Thomas" Riker shows up in Deep Space Nine, impersonates his brother, and steals the Defiant for a mission with the Maquis, making him at least seriously misguided. (He's right about the hidden Cardassian fleet, however.)
In Star Trek: Voyager, the Emergency Medical Hologram on the Evil Counterpart ship U.S.S. Equinox has had his "ethical subroutines" removed, making him an Evil Twin of the Doctor on Voyager.
"Skin", "Nightshifter", and "Monster Movie". The latter two don't really use this trope, but "Skin" prominently features a shapeshifter who becomes an Evil Twin of Dean.
Then there's the actual evil twin in "Simon Said". Sam and Dean are investigating a case where someone is using mind control to make people commit suicide. They find a guy named Andy who has mind control powers, but it turns out that the one who's actually making people off themselves is his long-lost twin brother, who has the same powers. Andy's response when he finds out? "I have an evil twin."
The Tonight Show with Jay Leno in the 90's had Jay playing different characters such as Iron Jay and Beyondo. The character of his that fits right in this trope is Evil Jay who appears at every full moon. Years before that, Jay Leno satirized the entire 'evil twin' trope when a guest on The Tonight Show Starring Johnny Carson. Leno had a marked-up TV Guide and showed what seemed like a dozen 'evil twin' themed shows for that one week. There was one on Hawaii Five-O. The bit wrapped with Dynasty (1981), which had Crystal replaced with her 'scheming lookalike', with Jay shouting, "Scheming lookalike? Scheming lookalike? It's an EVIL TWIN!". This trope is so endemic in television that perhaps we should be asking which shows never did it.
The Twilight Zone (1959): "Mirror Image" has the protagonists haunted by apparent malevolent doubles. Somewhat averted, as the seeming evil doubles do little more than watch their counterparts, sometimes smiling darkly.
The series plays pretty heavily on this trope, as Elena learns that her identical-appearing ancestor Katerina Petrova is alive and regularly killing people as a vampire named "Katherine", and both are part of a supernatural heritage of reincarnated Doppelgangers. Over the entire show, lead actress Nina Dobrev plays three versions of the Petrova Doppelgangers — all of whom eventually make out with fan favorite Elijah!
In the Season Four episode "American Gothic", Impersonating the Evil Twin is done to entertaining effect as Nina Dobrev plays No-Humanity-Emotionless Elena sitting across from Katherine in a lunch booth and does a workable impression of her own acting, but she needs to try a few times to capture "just the right level of contempt and hidden insecurity."
Silas to Stefan. Stefan is the doppelganger of Silas. Therefore, Silas is the Evil Counterpart to Stefan, who is the Good Counterpart.
In a Wizards of Waverly Place episode, Alex gets her replica out of a picture, using a special machine. Their lines suggests that Alex is actually thebadone of the two:
Alex: Goodness. I do look good in that dress. (she turns around) Baby Rockford, put that dress on, we got a fashion show to save.
Alex's replica: No! I like this dress...
Alex (turns to her replica): Alex, can I talk to you over there for a second?
Alex's replica: Sure! (she walks away)
Alex grabs a heavy object from a shelf, then follows her, with a dark scowl on her face.
WKRP in Cincinnati did it with Venus Flytrap being suspected of crimes that were committed by a pimp-dressed Evil Twin complete with the obligatory goatee.
In the 1990s Zorro series, Don Diego has an evil (though not identical) twin. Also, the evil Alcalde is at one point replaced by his identical twin, who raises the suspicion of the other characters by being somewhat less evil than the real Alcalde.
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