Gunn (1967)

Peter Gunn investigates the murder of Scarlotti, a mobster who once saved the detective's life. The primary suspect appears to be Fusco, who has taken over. In the middle of the investigation, an unclothed woman calling herself Samantha shows up at Gunn's apartment. As the case proceeds, more and grislier criminal activity occurs, including the bombing of Mother's, one of Gunn's hangouts. Finally, Fusco gives Gunn a deadline to prove the mobster didn't kill Scarlotti - or else Gunn will be killed.