Il Diavolo nel Cervello is a 1972 Italian psychological thriller directed by Sergio Sollima. Oscar (Keir Dullea) returns to Italy and reconnects with his former lover, Sandra (Stefania Sandrelli), whose son Emiliano is mute after witnessing his father's murder. As Oscar investigates the family's dark past, he uncovers hidden secrets and a web of deception surrounding the tragedy.