Black Cat #3

The Black Cat investigates the murder of actor Donald Rolman at Century Studios, where a dog was trained to kill him on cue during a film shoot. Dog trainer Quentin Harcourt confesses to the murder, claiming Rolman owed him money, but the Black Cat reveals that Harcourt used a silent dog whistle as the signal—a sound recorded on the film that she discovered by analyzing the picture being shot. After extracting this confession, the Black Cat subdues Harcourt and restrains him for police arrival.