Young Treasury Agent Eliot Ness arrives in Chicago and is determined to take down Al Capone, but it's not going to be easy because Capone has the police in his pocket. Ness meets Jim Malone, a veteran patrolman and probably the most honorable one on the force. He asks Malone to help him get Capone, but Malone warns him that if he goes after Capone, he is going to war.

The hard-boiled saga of hair-trigger cop Lieutenant Mike Torello and his obsessive pursuit of ruthless gangster Ray Luca.

A family moves from an affluent Chicago suburb to the mixed inner-city neighborhood where the father grew up, with the idea of giving the kids, who are becoming materialistic snobs, the feel of a big city environment.