Vince Giordano and the Nighthawks

With his holdings in Atlantic City lost, Nucky decides to go for a swim in the ocean. Meanwhile, in New York, due to Nucky's manipulation of Mayflower stock, Kennedy's business associates are nervous that repeal will not happen, and begin unloading their shares. Kennedy suspects Nucky's involvement, but Margaret convinces him to short sell his own shares. Margaret meets Nucky to inform him of her success, and it appears that they will rekindle their relationship but are interrupted. Nucky later returns to Atlantic City, intending to leave the city forever. He goes and meets Eli, gives him some money, and encourages him to return to his family. He then meets Gillian in the sanitarium, telling her the most he can do is set up a trust fund for her when she is released. However, it's revealed that Gillian has already been forcibly sterilized. Back in New York, Luciano and Lansky gather crime bosses from New York and all around the country and form the Commission, a singular body will mediate relations between all crime organizations in the country. Luciano also tasks Bugsy with killing Narcisse, and he is publicly assassinated in front of his church. In Chicago, Capone is served a court summons when the authorities manage to obtain his ledgers. While he publicly boasts that the charges of tax evasion won't stick, Capone says goodbye to his son before heading to court, where D'Angelo is waiting for him. Back in the past, Deputy Nucky finds out Mabel has miscarried, much to his shock. He is then summoned to his family home, where he physically beats his father for hitting his mother again, and warns there will be consequences if harm were to come to his mother again. After returning to Atlantic city, Nucky comes across Gillian again, who is participating in a parade. The Commodore promotes Nucky to Sheriff, and his first task is to deliver Gillian to him. Nucky reluctantly approaches Gillian, telling her that the Commodore is willing to take her in, and promising that he will look out for her. Back in the present, Nucky comes across Joe Harper again. Harper reveals that his real name is Tommy Darmody, Jimmy's son and Gillian's grandson, and shoots Nucky three times before being restrained by the police. As Nucky dies, he sees a vision of a younger version of himself swimming in the ocean and catching a coin.

Seven-year exile Eli Thompson has hit rock bottom, now a perpetual drunk and working as a debt collector for the Chicago Outfit with George Mueller, who is now one of Capone's veteran members. Mueller's life is starting to unravel as well, as the tension at home becomes evident through the strained exchanges with his wife and children. Gillian Darmody has gone completely clean during her forceful installment at a women's sanitarium, and begins planning how to get out. Eli's son Willie Thompson is now pursuing a career as a prosecutor, but with a possible ulterior motive. Nucky sits down with retired Chicago boss Johnny Torrio to discuss recent events, and Torrio arranges a meeting between Nucky and Maranzano. Luciano, Lansky, Siegel and Tonino meet to discuss their next move, with the former uneasy about Tonino based on his treacherous past. Nucky later sits down with Maranzano and Luciano, but in doing so recalls Tonino's culpability after seeing a boardwalk caricature in memory of old flame Billy Kent. After the Maranzano meeting, Nucky arranges a private meeting with Tonino, who warns him that Luciano is plotting against him. When pressed by Nucky, Tonino offers his loyalty whenever Nucky should ask. Later that evening, Lansky is rushed outside to find a dead Tonino thrown on his steps-murdered in open acknowledgement of Lansky and Luciano's murder attempt on Nucky in Havana, as well as vengeance for Tonino's part in Billy's death.

Chalky confronts Nucky at gunpoint and demands they get rid of Narcisse. Richard asks Nucky to disclose the location of Jimmy's body to keep Gillian in jail; in return, Nucky employs him for a hit. Richard sends Julia, Tommy, and Paul to his sister's. Nucky tells Narcisse that Chalky wants to meet. After an attempt on Torrio narrowly fails, he hands over his entire operation to Capone. Knox/Tolliver sets up an eavesdrop for the big meeting but no one shows; Eli's called to the Albatross, where Nucky puts a gun to his head until Willie intervenes. Tolliver confronts Eli in his home; they fight and Eli beats him to death. Chalky meets Narcisse at the Onyx but his bluff of providing Daughter's whereabouts is met by Narcisse's revelation that he has his daughter Maybelle. From his sniper position, Richard hesitates long enough that, when he pulls the trigger, Maybelle has moved to the table and into the shot; she is killed and Richard is mortally wounded by one of Narcisse's men. Narcisse is arrested and turned by Hoover into an informant on Marcus Garvey. Chalky retreats to Havre de Grace. Nucky sends Eli off to Chicago, where he is met by Van Alden. Richard, imagining his reunion with his new family in Wisconsin, dies peacefully under the pier.

Sally discovers heroin being slipped into shipments by Luciano and Lansky, at Masseria's behest. Chalky fails to kill Narcisse and is wounded. Margaret does an insider-deal for Rothstein in return for new lodgings. Capone, while trying to nudge Torrio into retirement, is saved by Van Alden from a tommy-gun ambush. Despite Tolliver's turning of Eli, Hoover's still uninterested in scotching the bootleggers' network. Nucky's forced into a deal with Narcisse after learning he's Masseria's partner on the heroin pipeline. Nucky promises Chalky to Narcisse but tells Mayor Bader to have cops slip Chalky out of town; too late, though, he discovers through Willie that Bader is in Narcisse's pocket. Chalky and Daughter narrowly escape the cops' clutches; Narcisse eyes Maybelle; Nucky, Eli, and Willie gather to decide the Thompsons' next move.

Gillian opens up to Roy; Julia proposes to Richard. Eager to assert his power at home, Van Alden tells Capone he'll kill O'Banion, but old business gets in the way. Narcisse punishes Daughter for her betrayal, pushing Chalky towards a war Nucky refuses to join. After other mobsters kill O'Banion at his shop counter, Van Alden takes $1000 over his dead body. Rothstein negotiates an insurance plan with Nucky. Chalky's daughter Maybelle discovers her father's affair with Daughter. Newlywed Richard asks Nucky for a job.

Tolliver hears about Willie's evasion of the law and pursues Eli as his means to ending Nucky's empire. Chalky busts up one of Narcisse's drug houses, with two-faced Dunn along for the show. Nucky's unpleasantly surprised when Sally rides up to Atlantic City with the new bootlegging delivery from Tampa. Narcisse employs Daughter Maitland to way-lay Chalky, but she can't bring herself to let Dunn kill Chalky and she stabs Dunn fatally in the back instead.

As news of Leopold and Loeb's arrest hits the papers, Al Capone, still in a raging grief over Frank's death, kills a policeman. Rothstein runs into Margaret at her work, which is not entirely above-board. Dunn deals with the church's concern about his heroin in the community. Willie drops out of college—infuriating his father—and turns to Nucky for work. After Johnny Torrio's arrested in a police raid on a distillery that he just bought from O'Banion, he gives Capone the go-ahead to kill the Irishman. Roy helps Gillian kick her habit but confesses to an obsession of his own. Agent Knox is actually Jim Tolliver, as Gaston Means has secretly known all along. Daughter Maitland reveals that her true allegiance is to Dr. Narcisse—not Chalky—for horribly personal reasons.

Nucky and Margaret have a strained meeting at Penn Station before he travels down to Florida. While investigating Eddie's death, Eli finds Eddie's key for the safety-deposit box at the bank, but isn't allowed access to it. Richard returns and comes across Paul Sagorsky after he's just received stark news from his doctor. Chalky draws closer to Daughter Maitland. Knox, pretending to be a Prohibition agent again, returns to Mickey's warehouse but can't escape Eddie's shadow. In Tampa, Nucky, Lansky, and Luciano meet with a new partner whom Bill's brought in. Julia tells Richard what she needs. Nucky gets into more than just business with a feisty, hard-drinking Sally.

Knox torments Eddie and reveals his dark past, pushing him to betrayal. Willie, arrested over the death of schoolmate Henry Gaines, phones Nucky. Gillian, desperate to regain custody of Tommy but losing her grip, turns to Dunn for a fix. Van Alden's enlisted by Frank and Al Capone to bust some Democrat supporters' heads; Frank's gunned down by deputized Chicago agents. Nucky has Willie stick to a false alibi, pays off the Philadelphia DA to free him, and leaves him with some avuncular advice shortly before Willie's roommate is arrested for Gaines' death. Eddie, back at the Albatross and guilt-ridden about betraying Nucky's trust, jumps out of his window to his death.

While in Tampa visiting Bill McCoy, Nucky becomes intrigued by Sally Wheet, a local bar owner. Roy has Gillian pretend to be his wife. Narcisse meets with Rothstein and, later, books singer Daughter Maitland for the Onyx Club. For a party at college, Eli's son Willie tries to finagle some booze from Mickey's warehouse. Richard finds himself in some trouble and his sister comes to his aid.

Chalky is pressured by Valentin Narcisse, a Harlem kingpin who knows what Dunn did. At home, Van Alden must deal with his stubbornly middle-class wife; at work, he has to deal with an angry Al Capone. Knox's true boss, it turns out, is J. Edgar Hoover. Before he leaves for Florida to visit an old friend, Nucky has to placate a frustrated Eddie and gives him a promotion. Valentin Narcisse puts an end to the conflict with the booking-agents wife by having her killed by his men.

It's a full-scale war in Atlantic City, and bodies are piling up on both sides. Operating out of a lumber yard, Nucky seeks to weaken the Rosetti/Masseria alliance while struggling to keep peace between Capone and Chalky. In New York, Luciano is framed by Masseria and Rothstein with the aid of corrupt police. Gillian makes a failed attempt to woo, drug and presumably kill Rosetti. Nucky strikes a deal with Rothstein to break Rosetti's strength. Chalky and Capone's army massacre Masseria's men as they are retreating to NYC. Richard storms Gillian's house and kills many of Rosetti's men. Rosetti escapes. Nucky then uses his political connections to settle a score with Rothstein. Richard gives Tommy a new home at Julia's, sacrificing his own relationship with her in the process. Rosetti meets with his three remaining henchmen but, on orders from Nucky, Gyp's main assistant stabs him to death while he is urinating on a beach. Nucky tracks down Margaret, who ends their relationship. A depressed Nucky then proceeds to walk the boardwalk where he is recognized by other pedestrians. While he is lonely, he has finally retaken control of Atlantic City.

Nucky maneuvers to avoid taking a political fall for the Attorney General, getting arrested in the process. Eli and Mickey visit Tabor Heights. Richard befriends an older veteran and his daughter, Julia. Gillian takes on a young lover, who she names "James". While her son longs for a male presence in the house, Margaret rekindles an affair with Owen.

Van Alden comes clean with his wife, but this backfires when they are visited by a Prohibition agent, forcing him to return to O'Banion's place. Margaret suffers setbacks while trying to promote her Women's Health clinic. Gillian seeks Leander's counsel in financing her bordello, for which she must either change her business model or let go of the past. Nucky enlists a reluctant Eddie Cantor to help Billie move up in the world. An attempt is made on Gyp Rosetti's life.

Nucky is set to receive an award by the Roman Catholic Church for his charitable work, but is suffering from insomnia and disturbing dreams connected to Jimmy's murder. Richard hears that Mickey is taking credit for one of his killings, while Nelson visits a speakeasy with coworkers. A young Benjamin Siegel is roughed up by Joe Masseria's men. Margaret negotiates a woman's health clinic in an audience with the Bishop. Gyp, having negotiated a temporary deal with Nucky, takes offense to an innocent farewell greeting.

Nucky has emotionally charged conversations with both Margaret and Eli over his business and the killing of Margaret's husband, leading to dramatic shake-ups in his personal and political lives. Jimmy meets with his dying father for the first time in years, and in the process reevaluates his relationships with Nucky and both his parents. Van Alden and Agent Sebso's working relationship is pushed to the limit by Van Alden's suspicions, ending after a definitive confrontation at a river baptismal. Angela prepares to flee from Jimmy to Paris, but learns her support system is not as strong as she believed.

Nucky asks for Margaret's assistance in backing his mayoral candidate with the passage of women's right to vote, leaving her conflicted about her expanding role as his mistress. Doyle switches sides back from Rothstein to Nucky, which leads him to conspire with Chalky against Lansky and the D'Alessios. Angela witnesses Jimmy's violent side against her photographer friend, and plans a better future with his wife. Van Alden grapples with his emotions, and has forceful encounters with both Margaret and Lucy.

Nucky is forced to readjust his political alliances because of a Democratic mayoral candidate promising to wipe out corruption. Jimmy returns from Chicago to deal with the D'Alessio gang, which has allied with Rothstein to import Scotch from Europe through Atlantic City, but is arrested by Agent Van Alden for the massacre in the woods. Margaret intercedes with Nucky on Madame Jeunet's behalf, while Angela finds her romantic and artistic ambitions halted by Jimmy's return.

Nucky visits Chicago for the Republican National Convention, where he finds himself intrigued by the candidacy of Warren G. Harding over more established candidates. The D'Alessio gang moves in on Nucky's territory at the expense of Eli, who has been watching over his brother's affairs. Margaret finds herself entangled in Nucky's business, while Van Alden struggles with his wife's desire for a child. Rothstein prepares for legal trouble over his role in fixing the 1919 World Series. Nucky asks Jimmy to return to Atlantic City to reinforce his position.

Nucky celebrates his birthday and uses the event to try and expand his influence over both the Mayor of Jersey City and a United States Senator. Margaret is tasked with delivering a dress to Lucy, and finds solace from her disillusionment by shoplifting lingerie. Chalky exacts revenge on a local Ku Klux Klan leader for a lynching. Jimmy and Capone expand their business operations by taking over territories from a local Irish gangster, resulting in vicious consequences for a prostitute Jimmy was fond of. Luciano takes an interest in Gillian while tracking down Jimmy at Rothstein's request.

Nucky makes a deal with African-American gangster Chalky White to handle the repackaging and distribution of bootlegged whiskey, a decision that quickly turns deadly for Chalky's gang. Margaret is given a job at a boutique through Nucky's connections, and crosses paths with his mistress Lucy. Agent Van Alden learns through a brutal interrogation that Jimmy was involved in the shooting in the woods, a discovery that forces Nucky to make a decision on Jimmy's future in Atlantic City.

Nucky is paid a visit by straight-arrow Agent Nelson Van Alden, who feels that Nucky has pinned a crime on a scapegoat. After using his recent windfall to buy presents for his wife Angela and mother Gillian, Jimmy is forced to pay Nucky a larger sum of money. Margaret is visited by both Van Alden and Nucky's brother, Sheriff Elias Thompson, each seeking a different side of her story as to the death of her husband. After the funeral of James "Big Jim" Colosimo, Chicago gangster Al Capone has a violent encounter with an inquisitive reporter. Nucky contemplates the upcoming election with his aging mentor, Louis "the Commodore" Kaestner.

At the dawn of Prohibition in January 1920, Enoch "Nucky" Thompson, treasurer of Atlantic County, hatches a scheme to make himself and his associates very rich by bootlegging liquor, entering into business with Arnold Rothstein and Charlie "Lucky" Luciano. Nucky is approached by beautiful and pregnant Margaret Schroeder, who wants his help finding her abusive husband a job. Jimmy Darmody, Nucky's former protege, returns from fighting in World War I with ambitious ideas about his future and he forges an unlikely alliance that could have serious consequences for both him and Nucky.