Expecting the usual loss, a boxing manager takes bribes from a betting gangster without telling his fighter.

When an employee at an illegal gambling den dies suspiciously, her sister, Nancy, looks into the situation and falls for Johnny O'Clock, a suave partner in the underground casino. Selfish and non-committal by nature, Johnny slowly begins to return Nancy's affection and decides to run away with her, but conflict within his business threatens their plans. As Johnny tries to distance himself from the casino, his shady past comes back to haunt him.

Struggling performers, Sothern and Skelton's lives are thrown off gear when they are caught with a bagful of hard cash robbed by a goon. With Skelton in prison, how will Sothern prove their innocence?

After a young woman is coerced into prostitution and her brother framed for murder by an organized crime syndicate, retribution in the form of an ape visits the mobsters.