A character has just moved into a small room the size of a closet. For added hilarity, it may even be an actual closet. This person barely has room to stand up in, so what's the first thing that happens? He gets visitors. Lots and lots of visitors. It often climaxes with one last person (preferably the comic foil, as per Margaret Dumont) opening the door and everyone tumbling out, Exploding Closet-style.
Originally done by the Marx Brothers in A Night at the Opera (seen right). All other versions of this gag are most likely an homage to the original, which was developed by Buster Keaton who reworked a similar sequence from his film, The Cameraman.
- In Academy Award-winning 1981 short Tango, a little boy climbs into an apartment to retrieve his ball. Then a nursing mother enters. Then a schoolgirl. Then a man carrying a package. Then more and more and more people—a nude woman, a man with a dog, a plumber carrying a toilet, etc—until 36 people are cycling through the tiny studio apartment.
- A Night at the Opera, of course: Groucho boards a ship and finds he has been booked into a stateroom so tiny that it barely holds him and his luggage. Inside his luggage, however, he finds stowaways Harpo, Chico and the movie's romantic hero. Then in come the maid, the electrician, some waiters with food, a girl looking for her aunt... It ends with Margaret Dumont opening the door and everyone tumbling out.
- They later took it Up to Eleven in A Night in Casablanca, filling a restaurant dining room not only with guests, but also tables and chairs.
- The Buster Keaton gag from The Cameraman involves just two people, Buster and a significantly bigger man. But it's a tiny changing room at the pool, so two is enough to make a crowd.
- Done in Brain Donors with Volare's dressing room. Appropriate, given that the movie is a remake of A Night at the Opera.
- Some Like It Hot has a scene aboard a train in which a passel of female musicians cram into Jack Lemmon's sleeping berth for a party, to similar effect.
- In Curse of the Wolfgirl fashion designer Thrix is preparing for a date and is visited by almost every non-villain character.
- The children's book The Mitten is about a mole who finds a lost mitten and climbs in to keep warm, followed by a rabbit, then a hedgehog, etc etc...
- In the Relativity story "Cricket", four people all end up in the same closet. The "door opens and everyone falls out" part happens, not because someone on the outside opened it, but because someone on the inside sees a giant spider and panics.
- The Suite Life of Zack and Cody - Actual Closet variant, completes the homage by having their mother open the door so that everyone tumbles out.
- Seinfeld - Elaine moves into a janitor's closet so she can order food, and Jerry and the gang drop by.
- Done in Yes, Minister with a really small sleeping compartment in a railway carriage and an endless series of visitors, one of whom is very fat.
- Star Trek: Deep Space Nine: a confirmed homage in "The Circle", though it's in Kira's quarters rather than a closet and it's pretty much friends barging in intending to wish farewell privately. All done in one take, though the final cut has reaction shots cut in.
- In an episode of Flight of the Conchords, Jemaine moves into a new apartment, which is really just an empty cleaning supply closet. The first thing he does is invite over everyone he knows for a housewarming party, which naturally spills out into the hallway.
- M*A*S*H does this in one episode when everyone has to cram into a two-man tent to conserve heat. Alan Alda's Groucho Marx impression shows up, of course, to quote the original's line, "Hello, room service? Send up a larger room!"
- The Bob Newhart Show has an episode where Bob and Emily prepare to embark on a two-month cruise, which climaxes with a huge crowd of people jamming into the Hartleys' cabin on the ship to see them off, including Howard, Jerry, Carol, Bob's entire therapy group, the ship's stewards... and one random guy who was walking down the hall and "was just suddenly sucked right in".
Howard: The first one who makes a Marx Brothers joke gets it.
- Sesame Street did this on the album Bert & Ernie Sing-Along, where Ernie brings a piano into the bathroom while Bert is taking a bath and invites the rest of the street gang over.
- In the video for "Girls Just Want To Have Fun" Cyndi Lauper invites so many people to her bedroom party that they fall through the door.
- Done in Animaniacs, in "Hercule Yakko". Dot name-drops "Night At the Opera".
- Includes a Visual Pun as well: a map of the continental 48 U.S. states on the door.
- Set up and subverted early on in Futurama. Fry initially stays in Bender's tiny, closet-like apartment (since robots don't need a lot of personal space)... until he finds out that the apartment's "closet" is actually a full-sized apartment.