In 1917 New York City, working-class neighborhoods are controlled by two Mafia gangsters, Don Faranzano and Don Masseria. Their violent rule of law has paralyzed the community with fear, and citizens consider themselves helpless. However, teenager Charlie Luciano aspires to undermine the town’s brutal dictators and replace their regime with egalitarian politics. When Don Faranzano assaults Charlie’s father, and Don Masseria has his nephew murdered, Charlie recruits his Italian-American companion, Frank Costello, and the two toughest Jewish boys in the neighborhood, Meyer Lansky and Benjamin “Bugsy” Siegel, to subvert the dons’ power. Following Charlie’s lead, the team pledges to protect the community and get rich at the same time. Five years later, the young men partner with Arnold Rothstein, a wealthy liquor salesman who takes Charlie under his wing and schools him in the art of illicit business practices. As Charlie distributes Rothstein’s “bootleg” alcohol throughout the city, he frequents a gambling club operated by his friend, Tommy Reina, and falls in love with a chorus girl named Mara Motes. When Charlie and his gang become millionaires, Don Faranzano and Don Masseira work against each other to lure the boys away from Rothstein, but the young men are wary of Faranzano’s anti-Semitism, and Masseira’s duplicity, and they choose to remain independent. However, the dons will not be denied, and one of Charlie’s liquor shipments is mysteriously hijacked by an unidentified gang. Blaming the dons, Rothstein cautions Charlie that the mobsters will find a way to take their business, and Charlie plans to send the men a warning. On the evening of the next shipment, Charlie’s gang ambushes the hijackers and orders them to stop working for the dons. However, Bugsy gets carried away and murders one of Faranzano’s henchmen. Although Charlie’s gang vowed to distance themselves from the two dons, they are now threatened with retaliation from Faranzano and must align themselves with Masseria for protection. Masseria agrees to shelter Charlie and his friends on condition that they hand over their liquor trade and kill Faranzano within six months. Charlie is obliged to consent, but he plots to undermine Masseria by curtailing the whiskey business and secretly infusing money into trade unions. When Charlie tells Arnold Rothstein about the scheme, the gentleman predicts gang warfare, but he is convinced Charlie will be victorious if he can secure Masseria’s confidence. Rothstein tells the boy that he must prove his allegiance to Masseria by finding a way to save the don’s life. Meanwhile, Masseria learns about Charlie’s plan. He has Rothstein murdered and orders Charlie to obey his authority. In response to Masseria’s new dominance, Charlie’s club-owner friend, Tommy Reina, advises the young man to align himself with Masseria’s enemy, Don Faranzano, and arranges a meeting. Despite warnings from his gang, Charlie meets his former adversary, Faranzano, only to realize he has been deceived. The anti-Semitic don is not interested in a truce and offers to shelter Charlie on condition that the boy approve the murder of his Jewish friends, Meyer and Bugsy. When Charlie refuses, Faranzano subjects him to torture, and slices his face with a switchblade, but Charlie survives. Reunited with his gang, Charlie plans to overcome Don Faranzano and Don Masseria once and for all by killing double-crosser Tommy Reina. The Reina assassination prompts a gang war between the two dons, who mistakenly blame each other for the murder. As the mobsters battle, Charlie remembers Rothstein’s advice about earning his enemy’s confidence and stages an attack in which he appears to save Masseria’s life. He uses his newfound alliance with Masseria to broker a backhanded deal with Faranzano; Charlie promises to kill Masseria if Faranzano ends the gang war and gives him a stake in his empire. With both dons under his control, Charlie orders Masseria’s assassination and is appointed a leadership role within Faranzano’s operation. However, Faranzano suspects Charlie is a threat and hires “Mad Dog” Coll to kill the young man. When Mad Dog breaks into Charlie’s apartment, he mistakenly murders his girl friend, Mara, who is hiding beneath Charlie’s bed sheets. Unaware of his error, Mad Dog returns to his hotel and is surprised when Charlie shows up to avenge Mara’s death. As Mad Dog escapes and races to Faranzano’s office, Charlie’s gang gains entry at the don’s high-rise building by pretending to be Internal Revenue Service agents, and hold Faranzano at gunpoint. Just then, Mad Dog charges inside, but Charlie is close behind, and he guns down the assassin. With Mad Dog dead, Charlie turns his attention to Faranzano and reminds the don of the assault on his father fifteen years earlier. Finally getting his revenge, Charlie orders his friends to throw Faranzano out the skyscraper window. In the wake of Masseria and Faranzano’s deaths, Charlie is next in line to become New York City’s Mafia boss, but he turns down the job. At a meeting with gang leaders, Charlie declares he is not interested in being a mobster because he does not wish to perpetuate violence. Instead, he advocates for the establishment of “The Commission,” a democratic board of leaders who vote on behalf of their community’s best interests, and the men unanimously elect Charlie as their director.