Assassination on the Tiber (1979)

"Assassination on the Tiber" is a 1979 Comedy movie directed by Bruno Corbucci and starring by Tomas Milian, Marina Ripa di Meana. A black-out occurs during the meeting of a gang of criminals. When the light is back one of them is found killed with a stab on his back and all the clues point to a penniless man who had an argument with the victim a short time before the murder.