Keira Woods' daughter mysteriously vanishes in the cellar of their new house. She soon discovers there is an ancient and powerful entity controlling their home that she will have to face or risk losing her family's souls forever.

Jane Morton, a psychiatrist from Dublin in deep mourning following the accidental death of her husband and son, is assigned to work on the case of Dorothy Mills, a teenaged girl in a small village who tried to strangle a baby. After miraculously surviving a car accident, Jane discovers a village darkened by strange events and meets a very nervous Dorothy, who swears she never touched the baby. After analyzing the teenager, Jane makes a diagnosis of multiple personality disorder until the day...