When road-weary Beth pays an overdue visit to her older sister Ellie, who is raising three kids on her own in a cramped L.A. apartment, the sisters’ reunion is cut short by the discovery of a mysterious book deep in the bowels of Ellie’s building. The book’s contents, spoken aloud, give rise to flesh-possessing demons, and Beth finds herself thrust into a primal battle for survival as she is faced with the most nightmarish version of motherhood imaginable.