

Tommy learns about a winner-takes-all mixed martial arts tournament called Sparta in which the winner will receive $5 million. The next day, Tommy enters a gym where, in less than a minute, he knocks out a professional fighter named Pete "Mad Dog" Grimes, in a fight which is filmed with a cell phone and later uploaded to the internet, where it goes viral. Paddy tries to convince him that he has changed, but to no avail.

Tommy had to run away from Paddy with his dying mother when he was just a boy due to Paddy being an abusive alcoholic, and has never forgiven him. Marine Tommy Riordan visits his father, Paddy Conlon, a recovering alcoholic who has returned to his Catholic faith in Pittsburgh, Pennsylvania.
