After becoming the most powerful mob boss in the country, Al Capone now finds himself locked up in a federal prison. Just over two years into his 11-year sentence, Capone is hand-selected to be transferred to America's newest and harshest maximum security prison: Alcatraz.
Meanwhile, the empire Capone left behind is dealing with a new problem. Prohibition has recently been repealed and one of the Outfit's most important sources of income dries up. With Capone cut off from all communication, his most trusted men, Frank Nitti, Tony Accardo and Paul Ricca, must keep his organization from collapsing. Nitti, the oldest and most established of Capone's inner circle, takes the reins of the Outfit.
With Americans flocking to theaters by the thousands, the movie business is raking in millions of dollars a month. To take advantage of Hollywood, Nitti recruits Willy Bioff, who has been extorting local cinemas by forcing their projectionists to go on strike unless theaters pay him a major fee. Nitti sends Bioff to Hollywood, where Bioff muscles his way into a high-ranking position in the film industry's largest union. He uses his power to threaten strikes on Hollywood productions unless the executives agree to pay the Outfit big money. With each shakedown bringing in upwards of $50,000, Bioff begins leading the Hollywood high life. His operation brings millions back to Nitti and Ricca.
While the Outfit leaders are enjoying success, one man is feeling looked over. For years, Accardo worked as Capone's bodyguard and enforcer. But with the mob kingpin in jail, Accardo is worried he'll be left behind if he doesn't start bringing in money himself. He breaks into a new racket in Chicago: slot machines. With help from Ricca, Accardo builds a network of slots in Chicago bars, earning up to $20,000 a year. By the end of 1939, the Outfit is bringing in more money than ever before.
In 1939, after spending more than seven years in federal prison, Capone is released. But the kingpin is a shell of his former self, as years of frequenting prostitutes has finally caught up with him in the form of a debilitating disease, syphilis. After rounds of experimental treatments, Capone moves to his estate in Miami to live under the care of his wife and family.
For five years, Bioff shakes down some of Hollywood's biggest studios. But as the flashy mobster gets greedier he's soon linked to growing corruption in the film industry and is arrested. To protect himself, he rats on his cohorts in the Outfit. When word gets back to Chicago that Bioff is talking, Ricca and Accardo ask Nitti to turn himself in. Desperate to stay out of prison again, Nitti takes his own life.
With Nitti dead, Ricca is convicted for the Hollywood extortion scheme and sentenced to 10 years in prison, leaving day-to-day control of the Outfit to Accardo. Ricca suggests Accardo reach out to Outfit gangster Sam Giancana for new revenue ideas.
Born and raised on Chicago's West Side, Giancana is a street-smart gangster with a knack for making money but a reputation for being a loose cannon. Giancana suggests moving in on a South Side racket known as the policy, an illegal lottery run by the African-American mob. The policy is broken down by neighborhoods, each with its own lottery known as a wheel and each run by local gangsters. The most successful policy king in Chicago is Giancana's old cellmate Eddie Jones.
Wanting to prove to Accardo that he's ready to move up in the Outfit, Giancana decides to get in on the policy rackets by kidnapping Jones. Accardo reprimands Giancana for acting without his approval but nevertheless strikes a deal with Jones that brings in $2 million a year.
With Accardo's blessing, Giancana takes over Jones's policy wheel and soon targets all the other wheels in the city. The Outfit's takeover of the Chicago policy racket will earn them upwards of $150 million.
On Jan. 25, 1947, Capone dies at the age of 48. After his death, Capone becomes an even bigger legend, inspiring countless books, movies and TV shows. Accardo is rumored to have sent Capone's wife, Mae, money to live off of until her death in 1986, a show of respect to America's most infamous gangster.
The empire that Capone built is now run by Accardo. Months after Capone's death, Ricca gets released from prison early and takes his place alongside Accardo as co-head of the Outfit. Accardo and Ricca decide to run their illegal earnings through the casinos of Las Vegas. There's just one problem: the New York mob is already there.