Eli discovers Eddie's key whilst investigating his death, but can't access what it opens, and Nucky gets some nuckie with Sally.
Nucky loses confidence in Rothstein as a partner. Willie plays a revenge prank on a fellow student that goes woefully wrong, and Federal agents continue to close in on Nucky's business.
Nucky reaches out to Joe Masseria after the battle with Rosetti. Gillian takes action to gain custody of her grandson. Eli's oldest son asks Nucky for career advice.
As Capone's cavalry rides in, the war starts: with firepower on the one hand and scheming to alienate Masseria from Rosetti, Nucky fights to get his business back and keep his life. Gillian takes on Gyp with her very own weapons, but sees herself overpowered; Richard poses as a one-man-army and seems to have more luck saving what's important. Meanwhile, Margaret has run off to face difficult decisions – not only about her unborn baby, but also about the future of her marriage.
Nucky doesn't get much time dealing with Margaret's affair when Gyp's men ambush him in the hotel. He flees with the wounded Eddie Kessler, and as there's nowhere safe to turn, it seems he'll be losing his last loyal man. With a price on his head, Nucky seeks refuge at Chalky's...
Gillian also has to suffer under Rosetti's willfulness when he chooses her club as a new headquarter, forcing her to lock Tommy in his room and finally even take measures against Richard, as she clings to her grandson against all common sense.
Owen makes plans with Katie as well as with Margaret, but those will turn out a whole different way after Nucky sends him to take care of Joe. Nucky too makes promises to his wife, speaking of a better future while trying to sort out his current business situation – being troubled with this, he turns down Chalky, one of his few allies left. On the political side, Gaston takes further action.
Meanwhile, Gyp has to deal with the uncertainties of nature, and Nelson "George Muller" Van Alden with the nature of uncertain dealings.
Gyp bribes the townspeople into silence while Nucky schemes to have him taken out of the picture for good. Gillian has words with James regarding Tommy.
Rothstein asks Gyp to be his new supplier but has other plans in mind. Gillian worries about her business.
Nucky and Owen end up trapped and hiding in a house from the feds after tracking down a thief who has been stealing from them.
Margaret starts a personal mission to start a women's clinic at the hospital. Nucky struggles with rumination over Jimmy. Van Alden finds it tough in his new position as a salesman.
To celebrate the New Year of 1923, Nucky decides to hold a flash New Year's Eve bash. Margaret helps him the hosting, despite their recent disputes. Tensions heat up when a hot-tempered gangster from New York arrives in town.moreless
With Nucky's trial right around the corner, Jimmy tries to make amends, but is it too late? Margaret makes a life changing decision and Van Alden flees to the Midwest.
Jimmy despairs because of his wife's murder which the police suspect him of committing. With Jimmy off the scene, his partners try to take his share.
Nucky heads to New York to hire a new lawyer after firing the last. After failing to get the black workers back to work, Jimmy asks Chalky for his demands and instructs Mickey to pay his debt to Manny.moreless
Nucky travels to Belfast in the hope of trading Thompson machine guns for Irish whiskey. Margaret receives some devastating news.
Nucky makes some family changes on hearing about the death of his Father. Jimmy's current success causes him to rethink his relationship with Angela whom has made a feisty new friend at the beach.moreless
Jimmy takes drastic measures to prove himself. Margaret visits her family in New York, whilst Nucky deals with Lucy and Van Alden in Atlantic City.
Van Alden battles with his conscience. Nucky's court case hits a hurdle while he tries to set up a liquor delivery to Philadelphia.
Nucky's attorney devises a plan that may help in Nucky's court case. Eli grows concerned over the Commodore's leadership abilities and Mickey's warehouse is next in Van Alden's sights.
Nucky asks the Attorney General for a favor when the Commodore stops alcohol reaching Atlantic City.
On realization that he might be losing control over Atlantic City, Nucky endeavors to discover which one of his men betrayed him. Rothstein puts Jimmy on hold in New York, with Lansky and Luciano still looking to do business. Dunn Purnsley gets more than he bargained for when he gets in Chalky's face in prisonmoreless
Election day arrives and Nucky prepares for change. Torrio sets up a potentially hostile deal between two bitter rivals.
Van Alden's increasingly conflicted emotions start to interfere with his work. Nucky has words with Margaret in regards to her support. Also, Angela is taken aback when seeing Jimmy's violent side.
Margaret tries to help Madame Jeunet with her money troubles by speaking with Nucky. Jimmy is forced to return to Chicago to deal with the D'Alessio brothers and Nucky gets ready for war with a rival factionmoreless
Jimmy becomes friends with a fellow veteran who lost half his face in the war. Luciano and Meyer Lansky make a deal with the D'Alessio brothers and Nucky deals with some unpleasant childhood memories.moreless