Nick Garcos comes back from his tour of duty in World War II planning to settle down with his girlfriend, Polly Faber. He learns, however, that his father was recently beaten and burglarized by mob-connected trucker Mike Figlia, and Nick resolves to get even. He partners with prostitute Rica, and together they go after Mike, all the while getting pulled further into the local crime underworld.

After two gang-related killings in "Center City," a suspect (who was framed) is arrested, released on bail...and murdered. Inspector Briggs of the FBI recruits a young agent, Gene Cordell, to go undercover in the shadowy Skid Row area (alias George Manly) as a potential victim of the same racket. Soon, Gene meets Alec Stiles, neurotic mastermind who's "building an organization along scientific lines." Stiles recruits Cordell, whose job becomes a lot more dangerous.

In 1940s Los Angeles, when womanizing composer Keith Vincent is found dead, the inquest concludes it was a suicide but police detective Joe Warne isn't so sure.

Charley Davis, against the wishes of his mother, becomes a boxer. As he becomes more successful the fighter becomes surrounded by shady characters, including an unethical promoter named Roberts, who tempt the man with a number of vices. Charley finds himself faced with increasingly difficult choices.

Larry Nelson, paroled from prison after serving nearly half of his thirty-year sentence, is determined to not fall into the clutches of the law again, and takes a quiet job at a country sanitarium. Thete, he meets and falls for a nurse, Charlotte Maynard, and he knows the only way to enter her web is to have a lot of money, for Miss Maynard is somewhat of a gold-digger.

Jack Early is a photographer who will stop at nothing to climb his way to the very top of the success ladder. On the strength of his sheer tenacity, he gets a job with a major newspaper, and it's not long before he's made a name for himself by charming a notorious crime boss, Nick Palmer, into allowing himself to be photographed. Palmer takes him under his wing, but Early decides to bite the hand that feeds him and sets Palmer and another crime boss, Colton, against one another.