Psycho is an American horror franchise that began with the novels Psycho, Psycho II, and Psycho House by Robert Bloch, and was popularised by the film adaptations Psycho, Psycho II, Psycho III, Bates Motel, Psycho IV: The Beginning, the 1998 remake of the original film, and additional merchandise spanning various media. The first film, Psycho, was directed by filmmaker Alfred Hitchcock. Subsequently, another film related to the series was made: an Alfred Hitchcock biopic, and two new novels, by Takekuni Kitayama and Chet Williamson, were released. Also, an independent documentary called The Psycho Legacy was released on October 19, 2010, mostly focusing on Psycho II, Psycho III and Psycho IV: The Beginning, while covering the impact and legacy of the original film.

Psycho is a 1960 American horror film produced and directed by Alfred Hitchcock. The screenplay, written by Joseph Stefano, was based on the 1959 novel of the same name by Robert Bloch. The film stars Anthony Perkins, Janet Leigh, Vera Miles, John Gavin, and Martin Balsam. The plot centers on an encounter between on-the-run embezzler Marion Crane (Leigh) and shy motel proprietor Norman Bates (Perkins) and its aftermath, in which a private investigator (Balsam), Marion's lover Sam Loomis (Gavin), and her sister Lila (Miles) investigate her disappearance.