Relatives and colleagues of reclusive writer Samantha Ballard track her to an isolated house in the California desert where they discover her traumatized and disturbed. She greets them with the grim announcement that they will die if they attempt to leave the house. After Samantha's ex-husband and his girlfriend suffer horrible deaths while trying to escape, the others realize that she was serious. They begin to scheme a safe way out even as the malevolent force that rules the house stirs the worst fears of each of them, causing them to wonder: Can they escape the evil house before their fears kill them all?