A Sub-Trope of the Odd Couple wherein the odd couple are twins, usually identical brothers or sisters. A prominent exception is actually in the former Trope Namer, The Patty Duke Show. It featured identical cousins, who were described as "One pair of matching bookends, different as night and day" in the Expository Theme Tune.
Anime and Manga
- Axis Powers Hetalia. The Boisterous Bruiser America and the Shrinking Violet Canada are only implied to be twins, but they fit in farely well.
- Bleach: The sweet Housewife Yuzu and the rough Bokukko Karin.
- Digimon Frontier: Kouji and Koichi. Kouji is arrogant and kind of a jerk at first, working by himself because he thinks the others will only drag him down. As time goes on, he shows a much kinder side. His Digimon forms are wolf-based and his element is light. Meanwhile, his twin is similar in appearance but far more soft-spoken and willing to be in the group once he's de-brainwashed. And, his Digimon forms are lion-based and his element is darkness (Dark Is Not Evil.)
- D.N.Angel: Riku and Risa.They even come out and say that their personalities are completely different. Risa is very girly and rather shallow, while Riku is tomboy-ish and more down to earth.
- Durarara!!: Mairu and Kururi Orihara actually invoked this. They actually flipped a coin to decide which girl got which trait. Strangely enough, their roles (Mairu as the Genki Girl and Kururi as The Quiet One) switch when they're on the internet. Even weirder is the fact that they don't consider themselves separate people.
- Ef: A Fairy Tale of the Two.: The Shindou sisters. Chihiro is a Ingenue, Kei is a Shorttank.
- Eyeshield 21: The Kongo twins Unsui and Agon. Unsui has a shaved head like a monk (it's sort of a theme at their school) is intensely hard working, diligent, cautious, a very good athlete and basically a decent guy. But Agon (with a distinctive dreadlock hairstyle) is the series' Jerkass, a Jerk Jock to the extreme (including the womanizing, which apparently started in middle school) who gets away with being a sociopathic thug, slacker and general all-around asshole because he is a talent seen only once in a hundred years.
- It emphasized by the fact that 'A' and 'Un' represent "beginning and end" aka birth and death.
- Glass Fleet's Non-Identical Twins Vetti and Cleo exemplify this trope. Though, their personalities are passed off as them having been raised separately, with the younger one subjected to mental and sexual abuse, giving him his screwed up personality.
- Kara no Kyoukai: Shiki and SHIKI. One is somber and speaks in Keigo, the other is somewhat carefree and speaks like a guy.
- Lucky Star: Kagami and Tsukasa. The former is a somber Tsundere while the other is a ditzy Cloudcuckoolander. When asked about this by Konata, they point out that they are fraternal twins.
- Monster: Anna and Johan Liebert. Anna's a nice, sweet girl who practices aikido and delivers pizza as a part-time job. Johan is the title character.
- Ranma ½: Towards the end of the manga, there is Pink and Link, identical twin girls from a village of herbalists that neighbours Shampoo's village of "Chinese Amazons" and who practice different branches of an unnamed "Martial Arts Herbalism", a fighting style that revolves around plants and herbalistic concoctions. Pink, who is usually smiling, is a wicked and vicious girl who loves to poison people. Link, who is usually frowning, is a kind and gentle girl who considers it her duty to heal those her sister hurts. Despite these opposite natures, they care for each other deeply and are capable of uniting with singular purpose when given motive... which means that, in their actual appearance in Nerima, they function more like Single-Minded Twins.
- Spirited Away: The identical twin sisters Yubaba and Zeniba. Yubaba is selfish and materialistic; Zeniba, while vengeful at first, turns out to be kindly and humble.
- Tenshi ni Narumon: Noelle (the light) and Silky (the darkness) as described by Mikael. Mikael and Raphael might also count
- There Beyond the Beyond: gives us twin boys both named Virid Visette Viridian, who are summed up quite nicely by their titles: "The Mad Prince" and "The Sane Prince".
- Trigun: Vash and Knives. One is a genocidal maniac and the other is a pacifist. That's pretty different.
- Vash is also all about how other people feel and love and peace, and Knives doesn't even do empathy for his twin with whom he has an effing psychic link.
- Vash acts like a fool whenever he can and Knives is all superiority and icy control except when his temper gets away from him. They do have a bit in common still, when you get past the good and evil divide. For instance, scary if you get them mad. Stubborn as hell. Charisma. Way of speaking, when serious, is even a little similar. Pretty good, when you consider they've been separated over a hundred times as long as they were together.
- When they were kids in the anime, one was unusually mature and one was goofy. No prizes for which. In the manga, they were much more similar, but Vash was more outgoing and Knives was more sensitive.
- Anime Knives goes off and cuts his own hair while Vash is getting his first haircut from Rem; when Vash finds him he says "if we stay the same, we won't have any individuality," even though they're pretty distinct already and even have slightly different coloring, because Viewers are Morons.
- Yu-Gi-Oh! 5D's: Rua and Ruka (Leo and Luna, respectively, in the dub) from Rua is a rowdy, cocky duelist who overestimates himself. Ruka is quiet, introverted and is usually the one to notify Rua when he goes too far.
- The original series' Yugi and Yami Yugi can be counted as this if you consider them twins (of the split personality/alternate guy living in your head kind), with a dash of Sibling Yin-Yang.
- ARAGO: Arago and Ewan fit this trope to a T.
- Saint Seiya has the twin brothers Saga (thoughtful, wise, just until his Super-Powered Evil Side kicks in) and Kanon (selfish, scheming, arrogant until he has a Heel Face Turn.) For major irony, Saga is the Gemini Saint, with Kanon inheriting his position once Saga dies.
- Hekikai no AiON: The twin sisters Shizuki and Yuzuki. Shizuki is a Manipulative Bitch and an Ill Girl, in the other hand, Yuzuki is a Ditz and a Dumb Muscle
- Rumiko Takahashi's one-shot The Samurai has identical twin ninja sisters, one of whom is a total nymphomaniac, while the other Does Not Like Men and Hates Being Touched. Woe be unto the person who confuses the latter for the former.
- Young Avengers: Caring geek Wiccan and hyperactive badboy Speed.
- Flash: Hyperactive, Fun Personified speedster Bart Allen (aka (Impulse) and his collected, scheming, evil clone Thaddeus Thawne (Inertia). Bart even mentions The Patty Duke Show the first time they meet, suggesting they switch places to befuddle their friends. Thad responds by punching Bart in the nose.
- In X-Men Noir, Thomas and Robert Halloway are, respectively, a know-it-all afflicted with Chronic Hero Syndrome and a crude, violent sadist. It's probably important to note that they were adopted by different families after their father died.
- Jezebel and Dinah in Blacksad: Dinah is a black bear (= dark brown) with a white patch on her chest, Jezebel a polar bear (= white) with a dark patch on her chest. Otherwise, they share face structure, and body and hair type. Personality-wise, Dinah is softer and Jezebel harder, although both have it in them to do what they need, if it's for righteous revenge.
- Gregory Stark and Tony Stark in Ultimate Avengers. Becomes a case of Cain and Abel.
- Eurotrip: The twins Jenny and Jamie are pretty different. Throughout the movie the phrase "worst twins ever" is repeated.
- Hellboy II: The Golden Army has Prince Nuada and Prince Nuala; while they are Half-Identical Twins in appearance, Word of God says they were intended to be as different as night and day in all other respects.
- The Parent Trap: In the 1998 remake, the twin girls, Annie James and Hallie Parker (Lindsay Lohan), are completely different. Annie is calm, reserved, and rather uptight while Hallie is relaxed, loud, outgoing, and a Big Eater.
- Susan and Sharon in the original, to a lesser extent.
- She's the Man: Sebastian and Viola. He's artsy and musical, and she's athletic and loves soccer. It's even lampshaded near the end of the movie.
- Star Wars: Luke is blonde, blue-eyed, calm, mild-mannered and naive; and is a mystical, religious Jedi Knight. Leia is brunette, brown-eyed, quick-tempered, sharp-tongued and worldly-wise; and is a shrewd, practical politician.
- The Star Wars Expanded Universe shows Luke having trouble teaching Leia to be a Jedi. What worked for him (he got a lot of Jedi qualities) won't work for her. Hot temper is not something a Jedi knight ought to have. Especially since she's pregnant with Han's baby while trying to learn.
- Markus and William Corvinus, from Underworld Evolution, were twin brothers who respectively became the first vampire and first werewolf. One is scheming and pompous, the other is near-mindless and savage. Unusual in that we never learn if they'd been genetically identical or not, as William is already locked permanently in his wolf-man form at the time the film is set.
- Rock star wannabe Roxy and Young Republican Jane in New York Minute.
- Jacob and Esau of The Bible. In fact one book of children's Bible stories even had the chapter title "Twins Who Were Different."
- Dawn and Eve of Piers Anthony's Xanth are literally as different as day and night, from the fact that Dawn is red haired and green eyed, and is like the morning, while Eve is black haired and eyed and is like the night.
- Amoret and Belphoebe in The Faerie Queene: The former was adopted by Venus, the Goddess of Love and Beauty, and became a Proper Lady. The latter was adopted by Diana, the Goddess of Maidenhood and the Hunt, and became an Action Girl.
- Occurs in Gordon R. Dickson's Childe Cycle series of novels and short stories, in the characters of Ian and Kensie Graeme. Both are Dorsai (Proud Warrior Race Guys). Ian is the epitome of the Warrior - seemingly aloof and intimidating by his sheer presence. Kensie is his polar opposite - warm, caring, social - everything that Ian is not. In the stories it's implied that together the two make up one individual.
- Ironically, it's Ian who's irresistible to women - without realizing it.
- Which is a tribute to Dickson's understanding of Female Psychology. Of course we women would be drawn to a dark, broody type over a sunny open one!
- Ironically, it's Ian who's irresistible to women - without realizing it.
- Both the books and TV version of Sweet Valley High, with the Wakefield twins Jessica and Elizabeth.
- The Eiran twins Eamonn and Grainne from Kushiel's Dart by Jacqueline Carey.
- Robert L. Stevenson's The Strange Case of Dr. Jekyll and Mr. Hyde: Dr. Jekyll and Mr. Hyde may be considered a variation of this trope.
- Shaun and Shem from Finnegans Wake probably count, but it's hard to figure out which is which, due to the book changing their names constantly. All you need to know is one is boring and dull, and the other is really creative and artistic.
- Specifically, Shaun is dull and conformist but successful in society, while Shem is a slovenly outcast but also an artistic genius.
- In the original Story Lottie and Luise by Erich Kästner (aka "Das doppelte Lottchen"), the titular twins had extremely different personalities, which made their place change all the more hilarious. Most film versions omit this, though.
- The Brothers Majere; easy going, heroic Boisterous Bruiser Caramon and intense, morally ambiguous Squishy Wizard Raistlin in Dragonlance.
- Tamora Pierce gives us:
- In the Tortall Universe, Alanna the down-to-earth Action Girl who dislikes magic, academic pursuits and social games, and Thom the fame-hungry career mage and scholar who thinks he's Above Good and Evil.
- In the Circle of Magic universe, Nia the shy, retiring one (with woodworking magic) and Jory the hyperactive, overeager one (with cooking magic).
- Eve and Alexandra in Master of the Game are a Cain and Abel crossover version—Alexandra is sweet, honest, and innocent, with no ambitions towards running Kruger-Brent, Ltd. Eve is consumed by ambition and the desire to be the center of everyone's attention, and starting from the age of five she's determined to kill and/or ruin Alexandra, who's in the way. (Incidentally, author Sidney Sheldon co-created the much gentler Trope Namer years before.)
- Owen and Porter from First Person Plural by Andrew Beierle. Owen is a book-reading drama nerd. Porter is a cheerleader-dating football player. Owen is gay, and Porter is straight. They are also conjoined twins sharing one body with two heads. This is incredibly awkward considering that Porter married a homophobic woman.
- Nicky and Alex in the Full House book series grew up to be different, one tough, one shy, although in one episode of the show their father was concerned that their personalities would turn out the other way around.
- Emmeline and Adeline March from The Thirteenth Tale, who are totally passive and excessively violent respectively.
- Madison and Vida Rocca from Power Rangers Mystic Force. Madison is calm and thoughtful, V is on a permanent sugar high and goes rushing into things with a mad grin.
- Sister, Sister, with Tia and Tamera Mowry.
- Two of a Kind and So Little Time, both with Mary-Kate and Ashley Olsen.
- The Suite Life of Zack and Cody, with Dylan and Cole Sprouse. Lampshaded in "Grounded on the 23rd Floor":
Zack: I swear, we're not related.
- The '80s sitcom Double Trouble. Identical twins Jean and Liz Sagal (younger sisters of Katey Sagal of Married... with Children) play identical twins Kate and Allison. Allison is serious and bookish; Kate is happy-go-lucky.
- Big Good Jacob and his unnamed fraternal twin in Lost.
- Scoundrels, Cal and Logan West, an incompetent burglar/criminal, and an intelligent defense lawyer, respectively. The characters are so different, you can barely tell they're played by the same actor.
- This is a remake of a New Zealand show, Outrageous Fortune, with Van and Jethro West in the same roles (also played by the same actor).
- The good and evil brothers in The Wanderer. Dispite both being played by Bryan Brown it isn't at 'all' difficult to tell Adam from Zachary, the evil cackle gives it away every time.
- iCarly: Sam and Melanie Puckett. Notably, Carly says she can't believe that they're sisters. They agree.
- Lee and Leah, the Separated at Birth twins from the British teen show The Gemini Factor, a rebellious boy and a teacher's pet girl, with a sprinkling of Twin Telepathy. They also tended to wear black and white, respectively.
- Katie and Emily Fitch from Skins. In the beginning Katie is portrayed as the shallow, popular, boy-obsessed Alpha Bitch, and Emily as the sweet, socially-awkward Shrinking Violet (and closet lesbian) who does everything her bossy sister says. But when both girls suffer a series of severe personal setbacks they handle it very differently, with Katie gaining a lot more depth and maturity, having to hold the family together virtually on her own, and Emily becoming more and more angry and destructive.
- Cathy and Patty Lane from The Patty Duke Show. "But they're cousins, Identical cousins all the way. One pair of matching bookends, Different as night and day."
- SCTV parodied the show, running promos for "Identical Bellhops", "Identical Cheese Hostesses" and "Identical OPEC Oil Ministers", all shoehorning their titles into the familiar theme song.
- America's Next Top Model: Amanda and Michelle Babin, who were contestants on Cycle 7. Michelle is tomboyish and more outgoing, whereas Amanda is more feminine and introverted. Michelle also came out of the closet during the course of the show, just to add another night and day difference to the mix.
- Tokio Hotel: Bill and Tom Kaulitz are identical twins, but dress and wear their hair differently, just to name one difference, to the point that some people don't believe they're identical. One of the more notable differences is Bill's focus on "true love" while (until recently) Tom was only looking for love of the one-night variety.
Oral Tradition, Myths and Folklore
- The Wood Elves of Warhammer Fantasy have Naestra and Arahan, polar opposite personalities in identical bodies produced when Naestrahan was split into two women due to an unknown event deep in the woods of Athel Loren. They ride a dragon.
- High Elf Heroes Tyrion and Teclis are identical twins with radically opposing personalities and skills. Tyrion is proud, fair, noble, athletic and well-spoken, while Teclis is dark, feeble, scholarly, caustic-tongued and bitter. The one is the greatest warrior and commander of his race but has no talent for sorcery, the other is a poor fighter but the most powerful living wizard in this age of the world.
- Warhammer's elves really seem to be prone to this trope, as another example can be found in the 5th edition Tears of Isha campaign pack, which focuses on the war between Calaidan and Kaldor, twin scions of the High Elf house Coraith, one of whom defects to Naggaroth and becomes an evil Dark Elf while the other inherits the family estates and continues their proud High Elven traditions.
- Ravenloft's Laurie and Gennifer Weathermay-Foxgrove are identical twin monster-hunters and proteges of Rudolph van Richten. Laurie is an exuberant tomboy, fencer and pistoleer who dresses like a man, while Gennifer is a demure, sober-minded wizard with closets full of conservative dresses. Also, Gennifer may be an unwitting lycanthrope.
- The Devil May Cry series Hothead Dante and calculating Vergil.
- Final Fantasy IV: Palom and Porom. Palom is the mischievous user of black magic, and Porom is the mild-mannered user of white magic.
- Porom isn't that mild-mannered though, when her brother is being naughty, she breaks into big sister mode and clocks him on the noggin'.
- The GetBackers game Jagan Fuuin The Mikado twins: Daisuke is very compassionate and sweet and easily befriends the main cast, whereas his identical twin Kyosuke is cold, emotionless, rarely speaks, and seems robotic. It's eventually revealed that the twins are the same person, namely Kyosuke, who, due to fear of their immense spiritual power, were split into two entities, the "body" and "soul". Daisuke was the soul, and once they were merged back into Kyosuke, he acted much like his "brother" did.
- Mother 3: Lucas is shy and withdrawn, while Claus is rash and reckless.
- Street Fighter: Hyperactive Yun and brooding Yang of the Lee Brothers.
- Tokimeki Memorial 2 has the twin sisters Miho and Maho Shirayuki, pictured above. Miho is a sweet, daydreaming girl who believes in fairies, and loves fortune-telling and plushies, and dreams of becoming a scenario writer of stories for children; Maho is a playful, blunt and mischevious street-wise girl, who enjoys fashion and window-shopping, and dreams of becoming a model.
- Vampire: The Masquerade Bloodlines: The Voerman sisters, stoic businesswoman Therese and emotional party-girl Jeanette, from You eventually discover Therese is a Malkavian, a member of a clan of vampires known for insanity, and her "sister" Jeanette is actually her Split Personality. With high enough Persuasion skill, you can convince the "sisters" to cooperate instead of one "killing" the other.
- The Warcraft universe. Malfurion and Illidan Stormrage, the night elf twin brothers.
- The Davis twins in The Sims 2: University are described verbatim as "different as night and day" within the game, yet they actually have identical personalities and aspirations. The only real difference between them is their appearances and what they like to talk about. Similarly, the Pleasant twins in Pleasantview are supposedly very different, but have very similar personalities.
- Adean and Briggid from Fire Emblem Jugdral. Adean is a sweet White Magician Girl who didn't train as an Action Girl because it simply didn't fit her kind nature, while Briggid was a stubborn Ladette that was first kidnapped and then raised among pirates.
- The Sims: Angela and Lilith Pleasant.
- Ace Attorney: Dahlia and Iris from the third game. Dahlia is a ruthless sociopath who has been using her cute and innocent image to get away with murder, literally, for years and Iris is sweet, gentle, and compassionate, and honestly fell for the lead character while posing as her sister because she needed him for a master plan but didn't want to be bothered with actually seducing him.
- Clannad: Kyou and Ryou. Long-haired Tsundere and short-haired easily-embarrassed sweetheart. Sound similar?
- Higurashi no Naku Koro ni: Mion and Shion Sonozaki. It's even more odd, when you realize that they're acting like each other, since they are each other.
- Tsukihime: Kohaku and Hisui. One is carefree, energetic and always smiling, while the other is silent with little expression.
- Also odd, when you consider that they switched places from when they were children. Hisui was originally carefree and cheerful, while Kohaku was shy and untalkative. Then they got older and It Got Worse for them (specially Kohaku, so Hisui buried her emotions to keep Kohaku stable while Kohaku hid her very darkened True Self behind a facade of happiness.
- Ember and Daystar in the Elf Quest visual novels. Ember is active, bold and like her name in looks and attitude. Brother Daystar is mystical and calm, and blond with pale skin.
- Its Walky: Fraternal twins Beef and Walky. Justified as Beef was actually switched at birth with Walky's real twin Sal as part of Mrs. Walkerton's Separated at Birth gambit, Sal and Walky later, after the truth was uncovered, and used to set up some Not So Different moments between the two of them.
- Sal and Walky again in Dumbing of Age despite not being raised apart this time around.
- LnM: L is energetic and childish, M is laid back and precocious.
- Molly and her clone / twin Galatea in The Inexplicable Adventures of Bob were raised separately. Both are brilliant, naive, and devoted to Bob, Jean, and each other. But while Molly is upbeat, friendly, and gentle, Galatea is paranoid and megalomaniacal.
- American Dragon: Jake Long: Oracle twins Kara and Sara. It's played around a bit as it is gothic Kara who foresees good events in the future while blonde and preppy Sara forsees the bad events.
- Angry Beavers: Dagget and Norbert, twin beavers.
- The Cramp Twins: The entire premise.
- CatDog: Cat and Dog, Conjoined Twins who are essentially the opposite of each other.
- Day and Night: The Pixar animated short actually took this literally.
- Dragon Tales: Zak and Wheezie, who are even very different colors!
- Elf Quest: Suntop and Ember actually brought the Media Watchdogs down on them when their creators tried to get an Animated Adaptation going. Turns out Saturday Morning Cartoons is not the time to reverse genders roles and have a spunky little girl and a mild, intuitive little boy.
- Or, for that matter, twins with different skin colors.
- What are you talking about?
- The Fairly OddParents: Wanda and Blonda.
- Kim Possible: Gemini identifies himself as being opposite his twin sister Dr. Director in every possible way, which is mostly accurate. They don't even look much like siblings, let alone twins.
- Muppet Babies: Scooter and Skeeter. They sang a song dedicated to this in the episode about opera.
- The Venture Brothers: Thanks to Divergent Character Evolution - Dean has slowly become a nervous, cowardly Non-Action Guy while Hank has evolved into a Ted Baxter who leaps into danger at the slightest provocation.
- The public perception of the Kray twins has traditionally had Ronnie, the younger twin, as pure Ax Crazy psychopath, and Reggie as quieter and more Affably Evil, even acting as something of a Morality Chain to his brother. There's not necessarily much evidence of this, but that just makes the fact that people want it to be the case an example of this trope in action.