On Chicago's South Side reporter Ed Ames finds the body of a dead girl. Her address book leads to a host of names of men frightened by her death but claiming never to have known her. Ames comes to know quite a lot, dangerously so.

Special prosecutor John Conroy hopes to combat organized crime in his city and appoints his cop father Matt as chief investigator. John doesn't understand why Matt is reluctant, but cynical reporter Jerry McKibbon thinks he knows: he's seen Matt with mob lieutenant Harrigan. Jerry's friendship with John is tested by the question of what to do about Matt, and by his attraction to John's girl Amanda. Meanwhile, the threatened racketeers adopt increasingly violent means of defense.

In 1903, Doctor Huntington Bailey meets a friendly older lady during a train trip. She tells him that she is going to visit her brother Nick and his lovely young wife Allida. Once in New York, Bailey hears that his train companion suddenly died. Shortly afterward, he meets the strange couple and gets suspicious of Nick's treatment of his wife.

Childhood chums Rocky Sullivan and Jerry Connelly grow up on opposite sides of the fence: Rocky matures into a prominent gangster, while Jerry becomes a priest, tending to the needs of his old tenement neighborhood.