Nucky deals with the fallout from Jimmy's rogue heist, sending Eli to sow the seeds of doubt in the mind of Margaret, who seeks help in the wake of her husband's demise.

An unlikely witness to the woods massacre threatens to expose the perpetrators, sending both Eli and Van Alden rushing to the hospital. Margaret starts a new job at an upscale French dress shop at the Ritz, while Chalky's team pays a heavy price for taking over Mickey Doyle's bootleg operation.

After the brazen robbery of one of his ward bosses, Nucky turns up the heat on Lucky Luciano. An emboldened Margaret stands up to Lucy at the dress shop and accepts an offer from Nucky to change her circumstances. In Chicago, Al's frustration over family issues spills over into his relationship with Jimmy, who scores points with Johnny Torrio for a bold power play involving Sheridan and the neighborhood of Greektown.

Nucky faces Election Day in Atlantic City and pulls out all the stops to keep power in Republican hands. Torrio brokers a discussion between Nucky and Rothstein to resolve their growing gang war, as well as Rothstein's looming federal indictment over the World Series. Both Jimmy and Eli voice their growing resentment towards Nucky, and find they have an ally in the Commodore. Van Alden seeks a sign on whether or not to leave Atlantic City, but receives unexpected news from Lucy. Margaret weighs new information about Nucky's first marriage and her uncertain future to make a final decision on her role in his life.

Nucky is shocked by an insurrection among his inner circle. An attack threatens Chalky's life and livelihood. Margaret deals with her son's problems. Angela vies for Jimmy's affection. Van Alden shows his wife around town.

After a dispute with his enemies, Nucky brings in a surprise guest speaker at a Memorial Day dedication for war veterans. Running out of options, Eli questions his allegiances, but it ends up sending him deeper into the hole. Nucky hires a new lawyer. Jimmy is taught a lesson by one of the Commodore's men that he won't soon forget. Richard decides to go hunting in the forest.

In the wake of a personal loss, Nucky solicits advice on his political situation from Arnold Rothstein, while Eli remains suspicious of his brother’s actions. Nucky finds himself in the unfamiliar position of showing gratitude toward a federal agent. Angela meets a new friend at the beach, and eavesdrops on her husband’s treachery. Nelson gets a nanny. Nucky approaches Owen with an overseas proposition. Jimmy flexes his muscles, at Mickey Doyle’s expense.

Esther Randolph's case is weakened by the sudden death of one witness and the sudden marriage of another. Jimmy turns away from the influence of others, including his mother. Nucky, acting the family man to Margaret, faces a difficult, bottom-line business decision.

Nucky makes a resolution; Margaret considers a hospital expansion; Gillian builds a new business; Van Alden stumbles onto a confrontation.

Rothstein vents to Nucky and delivers a message to Gyp. Gaston Means sees an opportunity. Billie gets a new co-start. Van Alden and Sigrid receive an unexpected visitor. Gillian worries about her business.

Gillian makes her peace with Jimmy's death; Van Alden attends a meeting with Capone and Torrio; Nucky makes an offer to Andrew Mellon; Margaret makes a stand on birth control; Nucky and Owen shop for a pony; Billie considers a future in film.

Nucky makes a deal with Rothstein as his war with Gyp Rosetti reaches its climax. Season finale.

Following his battle with Gyp Rosetti, Nucky makes a peace offering to Joe Masseria while working the odds with Arnold Rothstein. While Chalky is busy running the Onyx Club on the Boardwalk, the impulsive Dunn Purnsley clashes with a booking agent. Fresh-faced Federal Agent Warren Knox arrives in Atlantic City to learn the ropes from Agent Sawicki. Gillian seeks custody of her grandson, Tommy, while trying to find a “good” man to keep the Artemis Club afloat. Eli’s college-age son, Willie, turns to Nucky for career advice. Al Capone enlists his brothers, Frank and Ralph, to help him expand his business in the Chicago suburb of Cicero. Richard Harrow returns to his violent ways.

Nucky heads to Philadelphia; Agent Knox detains Eddie Kessler to obtain information about Nucky's organization; Gillian tries to score a fix; Van Alden is recruited by the Capones.

Nucky’s shipment from Florida arrives with some unexpected cargo. Eli is backed into a corner after Agent Knox uncovers some new dirt on the Thompsons. After talking things over with Nucky, Willie reconsiders his recent life choices. Chalky throws down the gauntlet toward Valentin Narcisse, upholding his leadership on the Northside.

Eli braces for the worst as Agent Knox launches his plan to bring Nucky down. Capone and Torrio reach an agreement in Cicero. Chalky looks to settle scores. Richard steps forward to save Tommy, at Gillian’s expense

Nucky reminisces about catching the Commodore's eye; Nucky joins Sally Wheet in Cuba; Margaret finds herself in the hot seat; Chalky tries to extricate himself from a difficult situation; Lucky Luciano sets a bold plan in motion.

Nucky plans to relocate to Manhattan; Margaret impresses Nucky and a grain company stockholder.