Couch gag

The Simpsons is an American animated television sitcom created by Matt Groening for the Fox Broadcasting Company. The opening sequence of The Simpsons features a couch gag; a "twist of events that befalls the Simpson family at the end of every credit sequence as they converge on their living-room couch to watch TV." The couch gag is a running visual joke near the end of the opening sequence and it is frequently used to make the show longer or shorter, depending on the length of the episode itself.

The couch gag changes from episode to episode and usually features the Simpson family's living room couch. A typical gag features the Simpsons running into the living room, only to find some abnormality with the couch, be it a bizarre and unexpected occupant, an odd placement of the couch, such as on the ceiling, or any number of other situations, such as to make a pop culture reference. Longer couch gags have sometimes been used to fill time in shorter episodes, such as in "Lisa's First Word", "The Front" and "Cape Feare". The show's 500th episode "At Long Last Leave" showcases each couch gag that was used in the series.

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