Police Comissioner Datti is investigating the murder of a female doctor whose murderer seems to be a thirty-fivish year old man. Soon another murder follows: Pianist Robert Dominici's girlfriend is found killed. The killer also challenges Datti on the phone and says he can't be caught since he has a secret which makes him invulnerable. In the meantime the clues seems to point in strange directions...
Robert Dominici
Hélène Martell
Inspector Datti
Susanna
Davide
Agent Marchi
Gloria Datti
Dr. Carla Pesenti
Dr. Vanni
Robert's Mother
Chief Physician
Agent Corsi
Father Giuliano
Inspector
Aging Expert
Unknown Role
Andrea
Danzil, a Cop
Swordmaster
Unknown Role
Laura, Venice Prostitute
Unknown Role
Mother (uncredited)
Man in Police Line-Up (uncredited)
Party Guest (uncredited)
Woman at Robert's Piano Concert (uncredited)
Man That Gets on Moped at Station (uncredited)
Man at Robert's Piano Concert (uncredited)
Man in Restroom (uncredited)