Hereditary is a 2018 American psychological supernatural 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 a demonic entity after the death of their secretive grandmother.

Psychological horror is a subgenre of horror and psychological fiction with a particular focus on mental, emotional, and psychological states to frighten, disturb, or unsettle its audience. The subgenre frequently overlaps with the related subgenre of psychological thriller, and often uses mystery elements and characters with unstable, unreliable, or disturbed psychological states to enhance the suspense, horror, drama, tension, and paranoia of the setting and plot and to provide an overall creepy, unpleasant, unsettling, or distressing atmosphere.