On leave in Italy, Lt. Tommy Knowlton falls in love with Jean Standish, who's not only married, but is the daughter of his submarine's commander. Friction between the two officers becomes intolerable once at sea and after Commander Toler is forced to abandon Tommy's best friend topside while the sub dives to escape enemy planes, Tommy is no longer able to contain his anger.

In 1920s Chicago, Italian immigrant and notorious thug, Antonio "Tony" Camonte, shoots his way to the top of the mobs while trying to protect his sister from the criminal life.