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.
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.
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.
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.
Annie, Joan and Lena need to find a way to work together to get Auggie back safely from Africa where he's been visiting Parker.
Alicia defends a judge facing misconduct charges and Kalinda visits Lana Delaney. Meanwhile, Cary makes a career change.
Alicia counsels a client whether to accept a strict plea deal. Meanwhile, Peter's newest political rival forces her back into the public spotlight.
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.