Agent Knox's plan to take down Nucky begins.
Chalky and Maitland hide out at his old mentor's, Oscar Boneau. Gillian contemplates selling her business for a life with Roy.
Chalky botches the hit on Narcisse and ends up wounded himself. Van Alden saves Al Capone when the building is lit up with Tommy gunfire, and Nucky is forced into dealings with Narcisse.moreless
Julia proposes to Richard much to his delight, prompting him to ask Nucky for work. Narcisse beats Maitland for her failure.
Agent Tolliver hears what happened with Willie at the school and uses it to blackmail Eli. Narcisse arranges with Maitland to kill Chalky.
Still grieving for his brother, Al, in a fit of rage kills a policeman. Rothstein and Margaret unexpectedly run in to each other, and Willie drops out of college, enraging his father.
Eli discovers Eddie's key whilst investigating his death, but can't access what it opens, and Nucky gets some nuckie with Sally.
Knox uses torture methods on Eddie, Al's brother is gunned down, and Nucky advises Willie to stick to his false alibi.
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.
While visiting Tampa, Nucky finds himself attracted to a local bar owner. Willie tries to pinch some alcohol from Mickey's warehouse, and Richard's sister comes to his aid.
Van Alden is ordered to keep an eye on the Capone's. Dr. Valentin Narcisse arrives in town with nothing but trouble with him. Eddie demands a promotion.
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.
Nucky himself reaches out for a powerful ally, while dealing with his mistress getting more attention than he's comfortable with. Meanwhile, Margaret has to concern herself not only with a living birthday present for her daughter, but also with some delicate feminine issues.
Eli invites Nucky to Easter dinner in the hope of mending a few fences.
The women's health clinic Margaret wants to set up runs into trouble. Gillian must make some changes to stay afloat and Van Alden finally come clean to his wife.
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.
Chalky tries to help his daughter, Maybelle. Nucky's emotional state leads to Gyp getting the upper hand. Eli gets out of prison, and Margaret's concerns on the sanitary condition of the hospital are not taken seriously.moreless
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.