Billy Behan is a poor 15-year-old kid in the 1930s Bronx. After the wealthy gangster Dutch Schultz takes him under his wing, Billy adopts the name of a neighborhood street and begins to work for the organization.
Billy is taught the ropes by Dutch's business associate Otto Berman and given menial chores. Dutch, meanwhile, is busy trying to beat a rap in court and also determine whether his partner Bo Weinberg has been betraying him. Even though he likes Bo, it is Billy who eventually helps prove that Bo lied about his whereabouts.
Dutch and his thugs take Bo captive and prepare to send him to a watery grave. Dutch proceeds to claim the attentions of beautiful Drew Preston, a married young socialite Bo has been seeing who clearly has a weakness for powerful, dangerous men.
Facing a court case in an upstate New York rural community, Dutch brings along his "protege" Billy and the sophisticated lady Drew to put up a front of respectability, ingratiating himself to the locals with good manners and money. While his boss Dutch stands trial, Billy's job is to keep an eye on Drew, a free spirit who likes having Billy's eye on her as she bathes nude in the woods.
Billy falls for her and admires his new boss, at least until witnessing first-hand exactly how ruthless a criminal Dutch really is. Unable to intervene on Bo's behalf, the best Billy can do in the end is try to save Drew's life and his own.