In 1973, sports handicapper and Mafia associate Sam “Ace” Rothstein is sent by the Chicago Outfit to Las Vegas, Nevada to run the Teamsters-funded Tangiers Casino, while Philip Green serves as the mob’s hotel CEO front man. Sam doubles the casino’s profits, which are skimmed by the mafia before taxes are paid. Mafia boss Remo Gaggi sends Sam’s childhood friend and mob enforcer Nicky Santoro, Nicky’s younger brother Dominick, and Frankie Marino to protect Sam and the skimming operation. Nicky’s volatile temper and Chicago criminal background eventually gets him placed into the Nevada Black Book, banning Nicky from every casino in Nevada. Dominick and Frankie have gathered their own experienced mob crew, and often engage in non-sanctioned shakedowns and elaborate burglaries instead.
Sam meets, and soon falls in love with beautiful hustler, dancer, and former prostitute Ginger McKenna. They soon have a daughter and marry, but their marriage is quickly thrown into turmoil due to Ginger’s relationship with her former boyfriend, con artist-turned pimp Lester Diamond. Sam has Nicky and his crew beat Lester when they catch him conning Ginger out of $25,000. Ginger turns to alcohol and develops an increasingly problematic drug addiction.
In 1976, Sam fires slot manager Don Ward for incompetence. When Ward’s brother-in-law, county commissioner Pat Webb, fails to convince Ace to rehire Don, Webb arranges for Sam’s gaming license to be denied, jeopardizing his position. Sam blames Nicky’s recklessness for ongoing police and Nevada Gaming Board pressure, and the two argue furiously in the Mojave desert. Sam has started hosting a local television talk show, and both Nicky and the Chicago bosses are upset that Sam is making himself such a public figure, bringing unwanted attention to their operations.
The Midwest Mafia bosses have put incompetent Kansas City underboss Artie Piscano in charge of overseeing all cash transactions. Piscano writes everything he knows about Las Vegas and the skimming operation in a private notebook, and rants about the cash costs in his grocery store. The FBI have wired Piscano’s store and are spurred into investigating Sam’s casino.
Sam seeks to divorce Ginger, who then kidnaps their daughter, Amy, planning to flee to Europe with Lester. Sam convinces Ginger to come back with Amy, but overhears her talking on the phone about killing him. Sam kicks her out of their home but later relents. Ginger approaches Nicky to get her valuables from Sam’s safe deposit box, and the two start an affair. Sam confronts and disowns Ginger, and ends his friendship with Nicky. Nicky finishes with Ginger when she demands he kill Sam. He throws her out instead. Drunk and furious, Ginger crashes her car into Sam’s (which is parked in the driveway) and retrieves the key to their deposit box. Although she succeeds in taking the contents of the box, the FBI arrests her as a witness.
In 1979, the FBI closes the casino and CEO Phillip Green eventually cooperates with the authorities. Artie Piscano dies of a heart attack when federal agents discover his notebook. The FBI approaches Sam for help by showing him photos of Nicky and Ginger together, but he turns them down. The bosses are arrested and put on trial, and start to arrange the murders of anyone who might testify against them and prolong their coming sentences. Ginger dies of a drug overdose, and Sam barely escapes death by a car bomb, suspecting Nicky to be the culprit. Before Sam can take revenge, however, the bosses, having grown tired of Nicky’s ongoing legal issues and angered by his apparent unauthorized attempt on Sam’s life, order Frankie and his own crew to ambush Nicky and Dominick. After being taken to an Indiana cornfield under the impression that they are attending a meetup, the two brothers are brutally beaten with baseball bats, covered in quicklime, and buried alive in a shallow grave.
With the mob now out of licensing fronts, the casinos are purchased by big corporations and demolished to make way for new and larger hotel casino attractions, which Sam laments. He retires to San Diego, and lives as a sports handicapper, in his own words, ending up “right back where I started”.