A subtrope of Mistaken Identity, this trope begins with Alice spotting Bob facing away from her. She approaches him. Either he turns around as she gets close, or she physically grabs him and spins him around...and surprise! It's not Bob, but some confused stranger who happens to look exactly like Bob, but only from Alice's angle. The audience usually sees the impostor from the same angle as Alice, so they are just as surprised as her when he spins around; in rare cases, the audience may instead see the impostor's face before Alice does, making it an instance of Dramatic Irony.
This flexible trope can be Played for Drama or Played for Laughs. In dramatic cases, the impostor can send Alice into a panic when she suddenly realizes Bob is nowhere to be found, or provide a cruel Hope Spot if Alice is searching for Bob already. In comedy, the humor may come from how completely different the impostor looks from Bob from the front; there could also be Cringe Comedy elements, if Alice says or does something embarrassing to the impostor (for instance, The Glomp) just before she realizes it's not Bob. The oblivious look-alike may also happen to wear Bob's exact Iconic Outfit by coincidence, if Bob has one, to make him a more convincing double.
Due to the often contrived nature of this trope, it can become prone to Trope Telegraphing. If a particular character Alice is looking for is only viewed from behind, and there's noticeable suspense as Alice approaches him/her, it's almost guaranteed to result in this trope, especially if said character is a plot-important one such as the Big Bad being (seemingly) encountered early on. The plot would end too quickly if Alice really did approach none other than Bob himself, and it needs to have drama, damnit!
Can overlap with Chair Reveal. Related to Identical Stranger. May also overlap with Mistaken for Object of Affection. Compare Face-Revealing Turn, which includes the spin but not the mistaken identity portion, and aims specifically at horror. May include a Butter Face character.
- Happens in the Durarara!! anime when Anri runs after who she thinks is her missing friend Mika and then calls out to her by taking her by the shoulder, before apologizing and running off in embarrassment after thinking she was mistaken at seeing the person who turned to face her. We find out later that Anri wasn't mistaken, but Mika simply had plastic surgery to look like Celty's head.
- In Sayonara, Zetsubou-Sensei, Chiri accidentally stabs Nozumo from behind because of this, and that she was trying to act like The Ditz.
- Darker Than Black has Kirihara "mistaking" from behind Kun (with whom she already was "accidentally acquainted") for The Black Reaper.
- In episode 65b of Tamagotchi, Doremitchi follows a girl from behind who looks exactly like Melodytchi save for her mouth, convinced it's the real Melodytchi.
- In episode 52b of Kamisama Minarai: Himitsu no Cocotama, Luckytama mistakes a bespectacled girl for Kokoro because she looks like her when viewed from the back.
- In Season 8 episode 12 of Happy Heroes, Careful S. is still forlorn over Kalo, his buddy from Planet Adeli, performing a Heroic Sacrifice to save Planet Xing from invaders. He then sees someone who looks an awful lot like the person he's thinking of from behind, and follows him before realizing he's actually just a merchant who was wearing a suit of armor.
- Pleasant Goat and Big Big Wolf: In Flying Island: The Sky Adventure episode 14, Weslie and Paddi hear someone calling for help from within a building, go in to check it out, and recognize the back of the woolly, pink-ribboned head of Tibbie. Except it's actually not Tibbie, it's just a bird girl who has the same head of wool and ribbons somehow.
- In one Calvin and Hobbes strip, Calvin is following his mom around the zoo. When he tugs on her skirt to ask her a question, she turns around... and it's not his mom. In fact, the woman isn't even wearing the same blouse as his mom, only the same skirt.
Strange woman: Are you lost? What does your mom look like?
Calvin: From the knees down, she looks just like you.
- In Tintin: Cigars of the Pharaoh, the Thompson twins attempt to arrest someone who from behind looks like Tintin in the bedouin outfit they last saw him wear. Turns out it's a completely unrelated guy, and what they mistook for Snowy's behind was a goat's. The incident sparks a war that causes Tintin to be drafted into the local military.
- In Bolt, when the titular character is lost in New York, he sees what he thinks is his arch nemesis the Green Eyed Man from behind. He tries to knock him out with a karate chop, but not only is the man not the Green Eyed Man, but the chop has no effect on him, which confuses Bolt, who has spent his life believing he has super powers.
- In Cars, Lightning McQueen gets separated from his truck Mack and looks for him. He thinks he sees him getting off the interstate, but after he catches up to him, it turns out to be someone else.
Lightning: You're not Mack!
Peterbilt: Mack? I ain't no Mack! I'm a Peterbilt, for dang sake! Turn on your lights, ya moron!
- In The Big Easy, Anne sees Bobby McSwain rummaging through the fridge, mistakes him for his brother Remy, and playfully pinches his ass.
- In Ferris Bueller's Day Off, while Principal Rooney is searching for Ferris Bueller (who has ditched school yet again), he mistakes a woman at a pizza parlor for Bueller from behind and yells "Your ass is mine!". She reacts by spitting her soda at him.
- In Species, Preston believes he spotted Sil at a bar but when he approaches the blonde girl and she turns around, it is somebody else completely. Watch the scene here.
- In Home Alone 2, Kevin loses track of his father in the airport and follows someone wearing the same coat, which lands him in the plane for New York. An unusual example because Kevin never does see the other guy's face, only the audience does.
- In Midnight, Tibor spots a girl in the streets wearing a shiny dress like Eve's. He pulls over and runs after her shouting Eve's name, but when he pulls her around, the girl turns out to be someone else.
- In I Now Pronounce You Chuck and Larry, Adam Sandler's character sees a hot blonde dressed as a Playboy bunny but when he calls out she turns out to be David Spade.
- In Conversations With Other Women, the Man during most of his twenties keeps running up to women from behind him that resemble his Love Interest.
- In Scott Pilgrim vs. The World, Scott calls out to Lucas Lee but is ignored. When he goes up and turns him around, it's not Lee but his Body Double.
- Don't Look Now ends with a horrific instance of this trope as the bereft parent thinks he can see his daughter and she turns out to be a female dwarf in a red coat carrying a hunting knife, with which she attacks him.
- This happens to Eddie when he is chasing Jessica Rabbit in Who Framed Roger Rabbit, and he ends up being chased himself.
- In Crocodile Dundee, Mick runs after what he thinks is his friend Sue, but as the person turns it's really just a man with long blonde hair and rather feminine clothing.
- Happens in Spaceballs, specifically the scene where Dark Helmet captures the stunt doubles of Lone Starr's group.
- In the Swedish classic comedy Äppelkriget, one of the Lindberg brothers tries to pick up a nice, tall, blonde woman at a night club. When she turns around she is revealed as a man, who is very much not amused.
- In Enchanted, Nathaniel deliberately points out a woman in a crowd who has similar hair to Giselle so that Prince Edward chases her while he goes after the real Giselle. The audience never sees the other woman's face, as Edward apparently caught up to her off-screen before moving on.
- A gag that was scripted for Superman: The Movie had Superman on a reconnaissance flight over Metropolis when he spots a bald figure among a crowd of people. Assuming it's Lex Luthor, Superman flies up from behind and grabs him by the shoulder, only for the man to turn out to be Telly Savalas, who greets him with a "Who loves ya, baby!" Superman, doing his best to hide his disappointment, acts as if he just came by to say hi.
- In Midway to Heaven, Ned Stevens becomes paranoid over his daughter Liz dating her boyfriend David. Ned thinks he's caught them drinking at a bar, but it turns out to be two people who just look like them from behind.
- SHAZAM! (2019): In a flashback to when Billy Batson was separated from his mother, he sees a woman wearing the same jacket she was wearing and confronts her, only to learn it's not her.
- Inverted in the Lord Peter Wimsey mystery Have His Carcass. Bunter thinks a man coming out of a room is not the same who went in, but when he turns, he recognizes the back and, deducing a disguise, follows.
- In How I Met Your Mother, Barney spends some time trying to figure out who's been mysteriously cockblocking him, and chases a mysterious blond out of a bar. The first blond he grabs and asks if he ever slept with her and then seriously screwed her over. He realizes it wasn't her, leaves, asks for her number, then leaves again and grabs the right blond.
- Parodied on an episode of Scrubs when Cox grabs Turk's shoulder from behind, only instead of Turk (bald black man), it's a petite, bald black woman. Later, JD goes to get Carla, only it's a mustachioed hispanic man with long hair and a mustache.
- An episode of Bones has a terrorist with a dioxin bomb about to blow up a peace conference. At one point Booth nabs who he thinks is the guy, but he turns around and it's someone else.
- In Angel, when Fred is on the run from her brainwashed friends, she loses them by taking off her jacket and giving it to a stranger with similar hair. In the time in takes her pursuers to see the stranger from the front, Fred manages to hide.
- In an episode of Game of Thrones, Arya is shown looking for her friend Jaqen among the Lannister soldiers at Harrenhal, so that she can request that he assassinate someone for her. Jaqen has red hair with some black and white streaks in front, and Arya initially grabs the wrong person, a random Lannister with red hair that he wore at the same length as Jaqen.
- The Outer Limits (1995): In "The Beholder", Patrick Tarloff is still getting used to regaining his sight and continually sees a mysterious, beautiful redhead everywhere he goes. At one point, he sees a redhead walking by and confronts her, but she turns out to be some ordinary woman.
- The 4400: In "Pilot", after being released from quarantine, Lily sees a man whom she thinks is her husband Brian. When she runs over to him and he turns around, she sees that it is someone else.
- The Twilight Zone (1959): In "A World of Difference", Arthur Curtis mistakes a little girl for his daughter Tina from behind.
- The Barrier:
- In one episode, Hugo and Julia being asked to watch their employer's nephew Sergio during what is technically time off results in Sergio visiting the part of town that isn't the enclave for the elites. When Sergio gets taken away by a member of the family from which he was abducted several years ago, there happens to be another child who looks like Sergio from behind in the area, resulting in Julia briefly mistaking the other child for Sergio.
- This is defied by a woman who saw her officially-dead son from behind for a few seconds, and is dead sure it was him despite only having seen the child from behind. Since her son turns out to indeed still be alive and the building in which he was seen has people involved in an secret child abduction operation working in it, chances are that it really was him.
- The music video for Smash Mouth's "I'm a Believer" has this happen repeatedly; he chases after someone with long blonde hair like his beloved's, but when the person turns around, it's some random dude.
- Minecraft: Story Mode: When the player character, Jesse, is looking for Ivor at EnderCon, they end up trailing and confronting a woman who looks exactly like Ivor from the back (same hairstyle, same outfit, but wrong gender). The woman takes offense to the sudden confrontation and Jesse quickly apologizes, although the woman is not so quick to forgive Jesse.
- In Sonic Adventure 2, Amy mistakes Shadow for Sonic and glomps him, much to his annoyance. While this particular incident is just the latest in a series (Sonic himself has already been falsely imprisoned because of getting mistaken for Shadow), no one really has an excuse even when viewing them from behind, since the colors of their fur are wildly different, and even their quills are styled differently
- Played straight in Girly, when Winter finds a faerie that is identical to Otra by behind.
- Shows up with hilarious results in Tripping Over You, where Dick mistakes Viola for Liam. Vi and Liam happen to look rather similar by default, and them having nearly the same haircut and Vi preferring typically masculine clothes reinforces this.
- In Yokoka's Quest, Mao mistakes another person for Copycat (justifiably, as it was a person who Copycat had previously mimicked), but realizes his mistake when he sees that they don't have Copycat's purple eyes.
- Cursed Princess Club: Princess Monika's magpie-like tendencies cause her to steal Gwen's handmade green dress after Gwen's first visit to the Cursed Princess Club. Later, when Prince Frederick catches a glimpse of Monika wearing the green dress, he assumes Monika is Gwen.
- Avatar: The Last Airbender:
- A variation occurs in the season 2 episode "The Swamp". While lost in the swamp, Katara has a vision of her dead mother facing away from her. Thinking the vision is real, Katara runs up, puts a hand on her mother's shoulder to spin her around... and suddenly it is not her mother at all, only a tall stump sticking out of the water.
- Deliberately invoked in "The Headband", when the police are searching for Aang at a secret dance party he hosted for a bunch of fire nation students. Their description is "a boy with a headband". When Aang escapes, the other kids put on headbands to confuse them.
- Ed, Edd n Eddy: Done twice in "In Like Ed". Eddy tries to hit on Nazz at a party, only for it to turn out to be Edd in disguise. A minute later, Eddy tries to talk to Edd and tries to stuff a piece of cake down his pants, only to find it was Nazz, who decks him in response.
- The Flintstones: In the dream sequence from "Rip Van Flintstone", an elderly Fred walks to his house and decides to surprise Wilma. From behind, it looks like Wilma, but when Fred grabs her to face him, it turns out to be a different woman, who accuses him of being a masher and sics her pet dinosaur on him.
- SpongeBob SquarePants: In the episode "Squidville", Spongebob and Patrick are trying to find Squidward in a crowd of look-alikes. Spongebob (and the audience) sees an octopus who looks like Squidward from behind, since he's wearing the same brown shirt. But when SpongeBob embraces him we see his face and he has heavy eyebrows and a big black mustache.
- Family Guy:
- In "The Most Interesting Man in the World", Peter, in a haste to bring Stewie home after leaving him alone at a playground, accidentally takes home a toddler that looks and dresses similar to him (except he has a normal-sized head), not noticing until he gets to the house.
- In "The New Adventures of Old Tom", Peter goes to look for Lois when she leaves him behind at the mall, but just finds Mort who's trying out a different look and got a new hairstyle and shirt similar to Lois.