Young Al Capone catches the eye of Johnny Torrio, a criminal visiting New York from Chicago. Torrio invites Capone to move to Illinois to help run his Prohibition-era alcohol sales operation. Capone rises through the ranks of Torrio's gang and eventually takes over. On top, he works to consolidate his power by eliminating his enemies, fixing elections to his advantage and getting rich. In his spare time, Capone courts the principled Iris Crawford.

Joe Buck is a wide-eyed hustler from Texas hoping to score big with wealthy New York City women; he finds a companion in Enrico "Ratso" Rizzo, an ailing swindler with a bum leg and a quixotic fantasy of escaping to Florida.