300 is a 2006 American epic historical war action film based on the 1998 comic book series of the same name by Frank Miller and Lynn Varley. Co-written and directed by Zack Snyder, with Miller serving as executive producer and consultant, the film is, like its source material, a fictionalized retelling of the Battle of Thermopylae in the Greco-Persian Wars. The plot revolves around King Leonidas, who leads 300 Spartans into battle against the Persian "God-King" Xerxes and his invading army of more than 300,000 soldiers. As the battle rages, Queen Gorgo attempts to rally support in Sparta for her husband.

Epic films have large scale, sweeping scope, and spectacle. The term is slightly ambiguous, sometimes designating a film genre and at other times simply big-budget films. Like epics in the classical literary sense, it is often focused on a heroic character. An epic's ambitious nature helps to set it apart from other genres such as the period piece or adventure film.