Hereditary is a 2018 American psychological horror film written and directed by Ari Aster in his feature directorial debut. Starring Toni Collette, Alex Wolff, Milly Shapiro, Ann Dowd, and Gabriel Byrne, the film follows a grieving family tormented by sinister occurrences after the death of their secretive grandmother.

Aster's work on short horror films, most notably The Strange Thing About the Johnsons, attracted the attention of A24, who greenlit Hereditary as his first feature film. Aster conceived it as primarily a family drama consisting of two distinct halves. Filming took place in Utah in 2017, with most indoor scenes shot on custom built sets on a soundstage to give the film a dollhouse aesthetic.

Hereditary premiered at the Sundance Film Festival on January 21, 2018, and was theatrically released in the United States on June 8, 2018. The film received positive reviews and made over $87 million, becoming A24's highest-grossing film at the time, until the release of Everything Everywhere All at Once in 2022.