In 1931, during the Great Depression, Michael Sullivan, Sr. is an enforcer for Irish mob boss John Rooney in Rock Island, Illinois. Rooney raised the orphan Sullivan and has come to love him more than his own biological son, the rash and unpredictable Connor. Rooney holds a wake in his home for the brother of an associate, Finn McGovern. McGovern is clearly agitated and insinuates that the Rooney family is responsible. Rooney sends Connor with Sullivan to meet with McGovern, under orders just to talk, but, after an altercation, Connor fatally shoots him, resulting in Sullivan gunning down McGovern’s men. Sullivan’s twelve-year-old son Michael Jr. had secretly stowed away in his father’s car and witnessed the event. Sullivan swears his son to secrecy and Rooney gets his own personal assurance. At a meeting with his associates, Rooney berates Connor for his actions when Connor halfheartedly apologizes for McGovern’s murder.Road to Perdition
That night, Rooney sends Sullivan to collect a debt from a speakeasy owner, Tony Calvino. Connor, jealous of his father’s preference for Sullivan over him and afraid Michael Jr. might talk, sends a letter with Sullivan for Calvino. When Calvino reads it, he reaches for his revolver, but Sullivan grabs it first and kills both Calvino and his bodyguard. When Sullivan reads the letter, it says “Kill Sullivan and all debts are paid”. Fearing his family is in danger, he rushes home. Connor has already reached the Sullivan home, murdered Sullivan’s wife, Annie, and younger son, Peter, and fled the scene. However, he has failed to kill Michael Jr., who had been detained at school for fighting and had hidden from Connor when he had reached the home.
Sullivan and Michael Jr. flee Rock Island and head to Chicago in hopes of meeting with Al Capone for work and learning the location of Connor, who has gone into hiding.
In a meeting with Frank Nitti, Sullivan offers to work for the Chicago Outfit in exchange for being allowed to kill Connor. Nitti rejects the offer, and Rooney reluctantly allows him to dispatch assassin Harlen Maguire, a voyeuristic crime scene photographer, to kill Sullivan. Maguire tracks him and his son to a roadside diner but fails to kill Sullivan. Realizing Maguire’s intentions, Sullivan escapes through the bathroom and punctures Maguire’s car tire before fleeing.