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.

故事发生在一八四二年六月的克兰福德镇，杰奇小姐（朱迪·丹奇 Judi Dench 饰）正在为了迎接她的新住客——故友的女儿玛丽（Lisa Dillon 饰）而进行着紧张而又精心的准备，对于这个墨守成规的小镇来说，没有什么消息能比一个陌生人即将到来更能让人们兴奋的了，“万事通”波洛小姐（伊梅尔达·斯汤顿 Imelda Staunton 饰）也是其中的一员。 布朗上校（吉姆·卡特 Jim Carter 饰）的大女儿杰西（茱莉亚·萨瓦哈 Julia Sawalha 饰）因为不愿意丢下孤苦伶仃的父亲而拒绝了多桩婚事，热情的玛丽决定帮一帮这位善良的姑娘。与此同时，“大龄剩女”卡罗琳（Selina Griffiths 饰）遇见了令她心动的哈里森医生（西蒙·伍兹 Simon Woods 饰），主动出击的她能够获得美满的爱情吗？