The Public Enemy
In the early years of the "Public Enemy" era, Dean O'Banion and other Irish mobsters of the previous decade served as the basis for many gangster films of the 1930s. James Cagney, for example, based his character on O'Banion and his lieutenant Earl "Hymie" Weiss in the 1931 film "The Public Enemy". Seasons 3 and 4 of the HBO series "Boardwalk Empire" featured a fictional version of O'Banion, portrayed by Arron Shiver.