Juvenile delinquents (Joyce Holden, Glenda Farrell, Harvey Lembeck) trap a neighborhood hoodlum in New York.

The arrival in a small mountain town of a dissheveled stranger launches a series of murders committed by some sort of animal. As the town doctor and his daughter attempt to help the stranger, the sheriff investigates the murders; and they uncover a sinister experiment involving two rogue scientists, a car accident victim, his wife and children, and a serum that causes a man to turn into a ravaging werewolf.

An ambitious coal miner is talked into becoming a boxer by his gambler brother.

Ex-police/army dog King inherits a fortune from an eccentric millionaire. But someone poisons him for his fortune. He gets to go back to earth as a human detective to bring his killer to justice and protect the girl who used to look after him.