Italian horror starring Donald Pleasence. While Police Comissioner Datti (Pleasence) is investigating the murder of a female doctor, pianist Robert Dominici (Michael York)'s girlfriend is found dead. The killer challenges Datti on the phone saying he can't be caught since he has a secret which makes him invulnerable. In the meantime the clues seem to point in strange directions. The cast also includes Edwige Fenech, Mapi Galan and Fabio Sartor.