A prequel is a literary, dramatic, or cinematic work that tells a story that precedes that of a previous work by focusing on events that occur before the original narrative. It is a work that forms part of a backstory to the preceding work. The term "prequel" is a 20th-century neologism from the prefix "pre-" (from Latin prae, "before") and "sequel". Like sequels, prequels may or may not concern the same plot as the work from which they are derived. More often, they explain the background that led to the events in the original, but sometimes the connections are not completely explicit. Sometimes prequels play on the audiences knowledge of what will happen next, using deliberate references to create dramatic irony.

Examples of prequels in film include "The Hobbit" trilogy, which tells the story of Bilbo Baggins before the events of "The Lord of the Rings", and "Star Wars: Episode III – Revenge of the Sith," which explains how Darth Vader originally became a villain.