There are three or more identical bags. One bag contains jewels or top secret documents, other bags contain other items of a random nature (and in wildly variable values) and one bag always contains underwear.
Through a series of random accidents and deliberate thefts the bags get switched. Repeatedly. The remainder of the story is a form of a farce based on people trying to get the "right" bag. The bags will change hands many times through many different players, and always on camera so that the audience can actually try to play the Shell Game and keep track. Unfortunately, they never actually open the bags to check that the contents are correct until they find themselves in utterly humiliating circumstances. Except for the person with the jewels: chances are they're the unlucky one who lost their underwear. Chances are once they see the jewels they won't really care too much any more.
The funny pretty much requires at least three bags. If there are only two then the players who are trying to get the bags will easily be able to hunt down the only other bag. But with three or more bags things just get insane.
A common joke in a Screwball Comedy.
There's also a variant where the wrong lunch was grabbed - apparently, in television shows, kids always pack their lunch in a plain brown bag instead of an easily-identified character on a reusable box or bag. Note that in this case three bags are not needed. The humor can come from the child getting raw giblets for lunch instead of their peanut butter and jelly.
Compare Switched at Birth, Shell Game. See also Stolen MacGuffin Reveal. When one character gets two or more objects mixed up, that's Unfortunate Item Swap. If there's only one bag but screwy items keep getting pulled out, that's Rummage Fail.
- One episode of Kochikame involved one of these, in which one of the bags contained photos of Nakagawa posing shirtless. Ryotsu and Nakagawa then spend the rest of the episode attempting to get that bag back (since, well, their chief has it and all...).
- Tintin was once framed for drug-running this way. The bad guy stole his real suitcase and replaced it with an identical one full of heroin.
- In The Broken Ear, he was framed by switching his suitcase for one containing Cartoon Bombs.
- In an Infinity, Inc. comic book story about Wildcat, Yolanda Montez put her torn Wildcat costume in a paper bag and left it on the counter in the hope that her mother would sew it up. The next morning, she finds out that her young brother took the bag with the costume in it while accidentally leaving his lunch in an identical paper bag behind on the way to school.
- Over the decades, Spy vs. Spy has gone through just about every conceivable variation on this trope, often with the decoy satchel having a bomb in it.
- In a classic The Far Side strip, two scientists have identical unmarked beakers. One of them loudly objects to the replacement of his dysentery culture with lemonade just as the other takes a drink. This strip is often posted as a serious safety reminder in various academic and professional labs: eating or drinking anything in a lab and/or out of labware can and has resulted in numerous, often tragic, variations on this exact scenario.
- FoxTrot: Jason mixes up his maths text book with Eileen. As a result, Eileen ends up finding an incredibly sappy love poem Jason had intended for his mother, and thinks it is for her.
- Happens with a matchbook containing a secret message in Sherlock Holmes in Washington.
- Blame It on the Bellboy is entirely based on this, with a hitman, a guy considering a real estate purchase, and a big schmuck there for a Medi-Date, each given the wrong envelope at a hotel in Venice. This results in the hitman thinking that he has to kill a woman there for a Medi-Date, the real estate buyer ringing the doorbell of some violent mobsters, and the schmuck expecting a sexy real estate agent to sleep with him.
- What's Up, Doc? and the four red-plaid suitcases, containing: A) Barbra Streisand's underwear, B} Ryan O'Neal's igneous rocks, C) secret government documents, and D) a fortune in jewelry. Of course those would never get confused.
- In the movie El Mariachi, the bad guys have the titular character mistaken for a hitman with a guitar case full of weapons who is trying to kill their drug lord leader, a situation that is only exacerbated when at one point, the two cases end up switched and the mariachi and the hitman end up with each other's stuff.
- The fantastic movie Eight Heads In A Duffelbag embodies this trope.
- The movie Push does this in a rather unusual way by adding in a bit of precognitive sleight of hand on top of multiple cases.
- Home Alone 3 starts with two identical shopping bags in an airport. One contains a toy car with a microchip stolen from the Army hidden inside it. The other contains French bread.
- The ultimate conflict in Police Academy 5: Assignment: Miami Beach comes about because a group of criminals who have smuggled diamonds into the country have placed the package in which the diamonds are concealed in a bag which is externally identical to Commandant Lassard's luggage, who is taking the same flight as the criminals. They end up claiming the wrong bags when they get to Miami, forcing the villains to try to track down Lassard and reclaim the diamonds.
- French mobster farce Oscar (1967) (with Louis de Funès) and its American remake (with Sylvester Stallone) contains a textbook example: 3 black satchels containing cash, jewels, and the former maid's unmentionables. It ultimately saves him when the police show up to arrest him. Toomey concludes that Snaps is using the bankers to launder money, and has his men look for the black bag as proof (not knowing there's more than one.) Fortunately for Snaps, Nora (the owner of the underthings) comes in and takes the more visible bag of jewels, leaving the bag of underwear for the police. Toomey then opens the bag, thinking it's the final nail in Snaps' coffin, and dumps its contents on the table, right in front of the reporters.
- The Jackie Chan film Legend Of Drunken Master starts with one of these. One package holds a stolen cultural artifact, the other holds a ginseng root that Jackie's master purchased on a shopping trip. The packages get swapped by accident when Jackie tries to smuggle the ginseng past customs.
- Averted in Fight Club: while the two suitcases are identical, the reason why is something entirely different...
- A dramatic two-suitcase version kicks off the plot of Fantastic Beasts and Where to Find Them. Newt Scamander, wizarding zoologist, has a Bag of Holding with a zoo of magical creatures inside. No-Maj Jacob Kowalski has a suitcase of pastries for the bakery he hopes to open. Some shenanigans involving a niffler at a bank later, Newt has the pastries and Jacob has the magical creatures. When he opens the suitcase at his apartment, he ends up letting several loose. At the end of the film, Newt also makes use of this to give Jacob some Occamy eggs (which are made of silver) as collateral for his bakery.
- Frantic. A married couple from the United States pick up the wrong suitcase on arrival in France, and are mistaken for the next stage in a smuggling ring. The wife is kidnapped for interrogation, and the husband spends the rest of the movie trying to get her back in exchange for what's in the suitcase.
- One happens in the Mexican superhero/wrestler film Neutron the Atomic Superman vs. the Death Robots, though despite claims to the contrary, they look nothing alike.
- Used in the very first Father Brown story with a package containing a valuable cross. Twice.
- A series of books based on Clue have all of the guests arrive at Mr. Boddy's mansion with identical-looking suitcases. Some contain valuables, and others contain valueless personal items. Given the characters involved, it should be no surprise that the ones who own the cheap items attempt to swap suitcases with the other guests, resulting in one character attempting to steal valuables but winding up with mouthwash.
- One Lord Peter Wimsey story has a bag of jewellery accidentally swapped for an identical-looking bag containing an actress's severed head.
- In James Blaylock's Homunculus, four of Keeble's mechanical boxes are eagerly sought by the heroes and by several different villains. In this case, all of them have value to somebody, but characters in search of a particular box's contents (an emerald, an oxygen-maker, a perpetual-motion device, and the title creature) keep snatching the wrong one.
- "Northwestward": We are informed of several offscreen attempts at robbery, as one or more people may have tried to steal/swap the suitcase containing Mr Wayne's emerald Batman ring.
- Done with sausages in 'Allo 'Allo! — at one time they had a sausage with a stolen painting, a sausage with a fake painting, a sausage with dynamite for La Résistance and an ordinary sausage for Herr Flick's dinner.
- Used in a more serious vein: the grifters often swap out the case full of money at the last second, save for a few episodes where the switch does not go as it should and they lose a lot of money, giving them an incentive to take on a riskier con to make up the cash.
- In one amusing episode, they switch out the other party's case only to realize that the other party had done the exact same thing to them as the two sets of grifters had been set up to go against each other.
- Fawlty Towers: Basil has to pick up a roast duck from Andre's restaurant in order to salvage his gourmet night. Unfortunately right next to the duck somebody sets down a trifle with an identical cover.
- An episode of Will & Grace used the brown paper bag variation of this: Will and Grace take Will's sperm sample to the fertility clinic, only to find out they accidentally brought Jack's lunch instead. Will races to Jack only to find that his bag has Karen's booze. Grace rushes to Karen and finds out that her bag has Rosario's floor polish. Will runs back to Karen's apartment to find Rosario, which leads to...
Rosario: Do not walk on the floor, I just waxed it.
- An episode of The Burns and Allen Show entitled "A Paris Creation" invokes the trope with two briefcases with the initials "G.B": one belonging to George, the other a nuclear scientist.
- A non-comedic example in the Nikita episode "The Next Seduction." Nikita swaps the suitcase containing a dirty bomb with one containing clothes in order to get it out of the hands of Gogol and Division.
- Variant in Monty Python's Flying Circus as a policeman attempts to frame an actor by blatantly tossing a paper bag down in his flat and pointing at it accusingly. When the bag is seen to contain sandwiches, the policeman exclaims "Blimey! What'd I give the wife?"
- Michael Westen on Burn Notice plays this with a couple of suitcases; one of which has a dangerous nerve agent, and the other, a "relatively harmless" mixture of strong pesticide, tear gas, and diesel fuel. He knows which one has the deadly gas, but Natalie the thief and her buyers sure don't...until he shoots the case.
- Adventures in Odyssey: It's two identical laptop computers in their identical cases — one being Whit's, the other being a top secret government computer full of military secrets stolen by Dr. Blackgaard — that get switched in a hotel shuttle van while Whit and Connie are in Chicago for a conference.
- The Goon Show:
- In "The Spanish Suitcase", the characters are trying to track down the title container, which supposedly holds the takings from a jewel robbery perpetrated by Major Bloodnok on behalf of Grytpype-Thynne and Moriarty. However, when the entire primary cast (except Minnie Bannister) have ended up in the same jail cell and Hotel Fred proprietor Henry Crun produces the suitcase, Bloodnok insists it only contains a change of underwear, and proves it by opening it and letting Grytpype-Thynne and Moriarty feel the contents. At the end of the episode, it is revealed that the actual suitcase of jewels was stolen by the porter at the Hotel Fred - narrator Wallace Greenslade.
- In the episode "Foiled by President Fred", the payoff involves a red sack and a blue sack. Which sack contains the real money and which contains forged notes? Eccles claims to know, but he's colour-blind. Or is he?
- One d20 Modern adventure ("A Funny Thing Happened at Carousel 14", which happens to be a homage to What's Up, Doc?) features no fewer than four characters with identical (gaudy and "unusual") bags, each with vitally important and for the most part incriminating contents. Compounding matters are two additional characters who plan to intentionally switch their own (again, identical) bags with someone else's. The Game Master is instructed to treat the adventure as a corporate espionage thriller, so that the players will be surprised when Hilarity Inevitably Ensues.
- In Oscar, there were three cases, having jewelry, cash, and lingerie. Angelo keeps thinking he's finally got the one with something valuable (money or jewels), only circumstances have given him the one with women's underthings... again. And because nearly all comedy protagonists choose the route most designed to embarrass them, he never bothers to check what's inside before dumping it out on the table in front of guests.
- One of the revelations of The Rashomon in Need for Speed: Carbon is the switching of two bags, one of them with money.
- Papers, Please: At one point the player is given two sets of secret documents, one to give to a friendly agent and one to give to his impostor as they pass through the checkpoint. The folders of them are identical, and you need to keep careful track of which as you shuffle them around your desk until your contacts arrive.
- Chaos On Deponia The motel has three bags. One belongs to the rival and is guarded by a not too bright robot. There are room keys too, but those are labeled.
- Hey Arnold!: Arnold, Gerald, and Sid find a shopping bag full of money, and decide to take it to the police station in the morning to collect a reward. But when Arnold arrives with the bag, it's full of birdseed. He tries to explain, "There was this old woman next to me on the bus, and she had pink hair, a peg leg, and one eyebrow. She had a whole bunch of shopping bags just like mine, and she must have taken my bag by mistake." Nobody believes him.
- The Flintstones episodes had this when Wilma's mother arrives at the Flintstone house carrying the same bag as the old bank robber lady had while she was staying there. The robber leaves to evade the police, taking the wrong bag, while Wilma's mother opened the bag containing stolen money and got arrested by mistake.
- In one episode of Tiny Toon Adventures there is a murderer on the loose who happens to look just like Hamton, at one point Plucky tricks Hamton is crawling into a sack which he then ties shut and tries to take him to the police, along the way he bumps into some bank employees who are transporting money and he grabs a sack of money by mistake, and when he presents the bag to the police and finding it full of money he promptly arrested.
- An odd example in My Little Pony: Friendship Is Magic; Twilight and friends are waiting to greet the games inspector, who they're told has a floral print suitcase. The pony they wind up with is an unnamed claustrophobic tourist with mustang blood. Hilarity Ensues.
- In The Smurfs Christmas Episode "The Magic Sack Of Mr. Nicholas", Gargamel captures a bunch of Smurfs while Chlorhydris steals Mr. Nicholas's toys. They bump into each other, swapping bags in the process.
- Bob's Burgers - Tina's siblings pull this bit on her classmate Tammy to retrieve her notebook of 'erotic friend fiction' and avoid public humiliation.
- Gravity Falls has Dipper and Mabel accidentally switch bags at the end of "Dipper and Mabel vs The Future", and due to being Locked Out of the Loop, Mabel gives the disguised Bill Cipher the dimensional rift, jumpstarting the End Of The World.
- In one episode of Jackie Chan Adventures, Jackie and Jade are trying to steal the snake talisman from the same museum Viper is trying to steal a valuable jewel from. One scuffle later and both of their identical-looking bags end up on the floor next to each other, triggering the accidental swap.
- A variation happens in Kung Fu Panda special Secrets of the Scroll, when Po's list of potential careers (doctor, janitor, comedian, and dancer), written on a scroll with jade handles, is accidentally switched with Tigress' list of four kung fu masters to find, which has identical handles. Tigress opens the wrong scroll and thinks that she has to find a doctor, janitor, comedian and dancer. Hilarity Ensues.
- In one episode of American Dad!, a significant jar of peanut butter is swapped several times between two identical bags. Eventually one falls into lava, at which point Steve learns that Stan had been trying to do this, but had thought it was a "magic bag" and didn't realize he had to do anything to make the swap, resulting in the jar being in the bag that fell into lava.