On the eve of Prohibition in 1920, Atlantic City county treasurer Enoch "Nucky" Thompson is looking to cash in. Prohibition may have outlawed alcohol, but in Nucky's world it has opened up highly lucrative opportunities for gangsters and rumrunners looking to provide "liquid gold" for a thirsty nation. In a city defined by notorious backroom politics and vicious power struggles, Nucky battles a relentless federal agent, ambitious underlings, and opportunistic rivals—including Arnold Rothstein, Lucky Luciano, and Al Capone.