Atlantic City, February 1924: After barely surviving an overthrow by gangster Gyp Rossetti, Nucky Thompson is laying low at the end of the Boardwalk.
But the calm will be short-lived, as Nucky faces new challenges, including a clash with the mayor, a battle with his brother Eli over Eli's college-age son, and the irresistible lure of lucrative - and perilous - opportunities in Florida.
From Terence Winter, Emmy Award-winning writer of The Sopranos, and Academy Award-winning director Martin Scorsese, Boardwalk Empire is set in Atlantic City during Prohibition, when the sale of alcohol became illegal throughout the United States, and chronicles the life and times of Enoch "Nucky" Thompson.
In the Season 4 premiere: following his battle with Gyp Rosetti, Nucky makes a peace offering to Joe Masseria (Ivo Nandi) while working the odds with Arnold Rothstein.
While Chalky is busy running the Onyx Club on the Boardwalk, the impulsive Dunn Purnsley (Erik LaRay Harvey) clashes with a booking agent.
Fresh-faced Federal Agent Warren Knox arrives in Atlantic City to learn the ropes from Agent Sawicki (Joseph Aniska) and Gillian seeks custody of her grandson, Tommy (Brady Noon), while trying to find a "good" man to keep the Artemis Club afloat.
Eli's college-age son, Willie (Ben Rosenfield), turns to Nucky for career advice as Al Capone enlists his brothers, Frank and Ralph, to help him expand his business in the Chicago suburb of Cicero.
Also, Richard Harrow returns to his violent ways.
Season 4 stars Steve Buscemi as Nucky Thompson; Kelly Macdonald as Margaret, Nucky's estranged wife; Michael Shannon as former Federal Agent Nelson Van Alden, caught up in gangland conflicts; Shea Whigham as Nucky's brother Elias, whose attempt to steer his son clear of Nucky's influence sparks fraternal tensions; and Jack Huston as disfigured war veteran Richard Harrow, who is searching for a new purpose in life.
Also starring this season are Stephen Graham as gangster Al Capone; Michael Stuhlbarg as gangster Arnold Rothstein, who's newly wary of Nucky; Vincent Piazza as gangster Lucky Luciano; Paul Sparks as Mickey Doyle, head of Nucky's bootlegging operation; Michael Kenneth Williams as Nucky's ally Chalky White, leader of the city's African-American community; Gretchen Mol as Gillian, battling demons from her past as she seeks custody of her grandson; and Anthony Laciura as Eddie Kessler, Nucky's longtime valet.
New cast members in Season 4 include Jeffrey Wright as Valentin Narcisse, a violent Harlem power broker who tries to muscle in on Chalky's action; Ron Livingston as Roy Phillips, a business and romantic prospect of Gillian's; Patricia Arquette as Sally Wheet, a Florida speakeasy owner; Brian Geraghty as Federal Agent Warren Knox; and Domenick Lombardozzi and Morgan Spector as Al Capone's brothers, Ralph and Frank.
Created by Terence Winter, Boardwalk Empire is executive produced by Terence Winter, Martin Scorsese, Mark Wahlberg, Stephen Levinson, Tim Van Patten and Howard Korder; co-executive producers, Eugene Kelly and Eric Overmyer; consulting producer, Dennis Lehane; producers, Joseph Iberti and Rick Yorn.