Jackie Cogan (Brad Pitt) is an enforcer, and when the mob's rules get broken, Cogan is called in to take care of business. This time a high-stakes card game has been held up by an unknown gang of thugs. Calculating, ruthless, businesslike, and with a shrewd sense of other people's weaknesses, Cogan plies his trade, moving among a variety of hoods, hangers-on, and big-timers, tracking those responsible, and returning "law and order" to the lawless Boston underworld.