Psychiatrist Dr. Ty Adams comes to the Sedah State Mental Hospital to film a documentary. While coming across self-assured and overconfident, Adams is secretly haunted by the death of his daughter. He strikes up a friendship with the facility's administrator, Dr. Samuel Delazo, playing an ongoing chess game with him. Adams is intrigued by a patient named Barnett (Eriq La Salle) who claims to be Satan and takes a personal interest in his case.