A grieving family veers toward madness in the new trailer for Hereditary. The horror film debuted earlier this month at Sundance and appeared on Rolling Stone's list of 20 best movies from the festival.

Hereditary opens with the death of Ellen Graham, which leaves her daughter (Toni Collette) and grandchildren in mourning. "It's heartening to see so many strange new faces here today," Collette says at the funeral. "I know my mother would be very touched, and probably a little suspicious. My mother was a very secretive and private woman.