Kings from across the continent of Westeros vie for the Iron Throne. As winter approaches, the cruel young Joffrey sits upon the Throne in King's Landing, counseled by his conniving mother Cersei and his uncle Tyrion, who has been appointed the new Hand of the King. But the Lannister hold on power is under assault on many fronts, with two Baratheons donning crowns, and Robb Stark fighting as the King in the North.

Chronicles the life and times of Enoch 'Nucky' Thompson, Atlantic City's undisputed czar at a time when Prohibition proved to be a major catalyst in the rise of organized crime in America. Season three begins on New Year's Eve 1922-23. The roaring '20s are about to start; though the economy is booming, alcohol has become scarce, competition is fierce, and gangster violence is heating up.

Atlantic City, February 1924: Picking up 8 months after the events of Season 3, Nucky Thompson is laying low at the end of the Boardwalk after barely surviving an overthrow by gangster Gyp Rosetti. But the calm will be short-lived, as Nucky faces new challenges, including a clash with a violent Harlem power broker, a battle with his brother Eli over Eli's college-age son, and the irresistible lure of lucrative- and perilous- opportunities in Florida....

As the season begins, encouraged by the Red Wedding slaughter in the Riverlands that wiped out many of their Stark nemeses, the Lannisters' hold on the Iron Throne remains intact. But can they survive their own egos as well as new and ongoing threats from the south, north and east?