Bottle episode

In episodic television, a bottle episode is produced cheaply and restricted in scope to use as few non-regular cast members, effects and sets as possible. Bottle episodes are usually shot on sets built for other episodes, frequently the main interior sets for a series and consist largely of dialogue and scenes for which no special preparations are needed. They are also commonly used when one script has fallen through and another has to be written at short notice.

The etymology of the phrase originates with a similar term used on the set of the 1960s Star Trek. Cast and crew members of the show use the phrase "ship-in-a-bottle episodes", for those that took place only on board the Starship Enterprise.

Bottle episodes are sometimes produced when a show has a mid-season cliffhanger or an expensive season opener/closer, to allow as much of the budget as possible to go to the more expensive episodes. Scott Brazil, executive producer/director of The Shield, described bottle episodes as "the sad little stepchild whose allowance is docked in order to buy big brother a new pair of sneaks". The popularity of the Friends bottle episode "The One Where No One's Ready" led the producers to create at least one bottle episode in each season. Several early episodes of The X-Files were conceived as bottle episodes, including "Space", "Darkness Falls", and the well-received "Ice", although these ran over budget.

Bottle episodes from Star Trek are known for occasionally becoming popular with fans. Examples include "The Tholian Web", "Journey to Babel" and "Balance of Terror". The phenomenon has persisted to a lesser extent in later incarnations, with "Duet" (Star Trek: Deep Space Nine) being celebrated by Startrek.com and Amazon.com—among other sources—as "[a]rguably one of the best episodes of Deep Space Nine and a jewel in the entire Trek canon".

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