Irish Eyes explores the relationship between two Irish-American brothers in Boston born to immigrant parents and raised in a rough, working class Irish neighborhood. After watching their father being gunned down in front of their eyes as children, Thomas and Sean Phelan grow up building their lives on opposite ends of the law. Thomas, the studious and responsible brother, creates a better life for himself through education and hard, honest work. Eventually, he builds a successful career as a US Attorney. Sean, the more rebellious of the two, gets caught up in a life of crime and rises through the ranks to become the head of the Irish Mob. Spanning from post World War II during the late 1950s through the Irish Mob wars of the 1970s and culminating in their adulthood in the 1990s, the story is set to the backdrop of backroom politics and the realities of the Irish Mob and its gang wars. The theme of the film simultaneously addresses the similarities between the two factions of law and crime while revealing the similarities between the two brothers.