There appears to be three prime suspects in the backstage of a theater where the murder of a blackmailing gossip columnist is committed. Sergeant Lane heads up the investigation when Detective Rocky King is ill with food poisoning.

Rocky is called to a rooming house because of a mystery involving three of the lodgers.

Famed chemist Dr. Sloan is found murdered and Rocky has three suspects to interview. Sloan's secretary Miss Merrick has been bequeathed the deceased man's estate and Rocky zeros in on the lady.

Three hours before Dayton Merrill is to be executed for murder, Inspector King receives a taunting phone call from a man who claims to have really committed the crime. Unable to get a stay of execution based on the man's confession, King and Detective Lane must re-investigate the crime and find sufficient evidence to save an innocent man's life.

A hotel guest is found murdered and Rocky is called to the scene to decipher to the case.

A member of a dating club is found dead and Rocky gets the case. His suspicions are aroused when he learns the deceased man was recently engaged to the secretary of the lonely hearts organization.

One of three owners of a radioisotope factory is killed and Rocky must uncover the culprit plus the reason for the crime.

A bodyguard of a wealthy industrialist is murdered and the police are called. Rocky must determine who the actual intended victim was before the case can precede.

A wealthy fisherman who was an expert is pulled from a boat and drowned. Rocky thinks it's murder with three possible suspects; the man's widow, the captain and the deckhand are all questioned.