The Commodore throws his weight around with the Coast Guard to disrupt the delivery of alcohol, which creates an opportunity for Owen to demonstrate his value to Nucky and a struggling casino. Meanwhile, a letter dredges up painful memories for Margaret; Nucky calls in a favor with the U.S. attorney general; Meyer and Lucky learn the price of power; and Lucy searches for ways to cure her loneliness.
Boardwalk Empire is a period drama focusing on Enoch "Nucky" Thompson (based on the historical Enoch L. Johnson), a political figure who rose to prominence and controlled Atlantic City, New Jersey, during the Prohibition period of the 1920s and 1930s. Nucky acts with historical characters in both his personal and political life, including mobsters, politicians, government agents, and the common folk who look up to him. The federal government also takes an interest in the bootlegging and other illegal activities in the area, sending agents to investigate possible mob connections but also looking at Nucky's lifestyle—expensive and lavish for a county political figure. The final season jumps ahead seven years, to 1931, as Prohibition nears its end.
Nucky plans to relocate to Manhattan. Margaret impresses Nucky and a grain company stockholder.
Nucky tries to hold onto his assets in Atlantic City. Willie and Eli become involved in Nucky's war.
Federal agents enlist the help of Eli and Van Alden to take down the Capone organization.
Chalky returns to Atlantic City. Nucky arranges a meeting with Maranzano. Eli reunites with June.
Nucky and Margaret find common ground in Atlantic City. Luciano encounters an old adversary.