Tony Accardo receives a phone call from Joseph P. Kennedy, asking the mob kingpins to use their pull with the Illinois union vote to help his son, John F. Kennedy, win the upcoming presidential election. In return, he offers to put an end to his son Robert F. Kennedy's investigation into Giancana and the Outfit. As election day nears, Kennedy's fight against Richard Nixon tightens, turning Illinois into a key battleground. Giancana delivers the union votes. After a close race, Kennedy is declared the victor. Just weeks after Kennedy takes office, his brother Robert is named Attorney General. To the Chicago mob's surprise, when Robert takes office as the new U.S. Attorney General in 1961, he makes his top priority going after organized crime ó and one of his primary targets is the Outfit. Weeks after, John F. Kennedy is shot and killed in Dallas. After his brother is assassinated, Robert steps down from his post as Attorney General and the investigation into organized crime is virtually dropped. The government begins an investigation into the assassination, with rumors already circulating that the mafia could have been involved.

In 1927, Prohibition agent Eliot Ness narrowly escapes a hit ordered by Al Capone. Determined to prove to Capone that he's not intimidated, Ness and his team of Untouchables execute a series of high-profile raids on Capone's breweries. Over the course of a few months, they destroy more than 200,000 gallons of beer, worth a modern-day equivalent of $134 million - and the newspapers cover it all. Capone lashes out against Ness in the press. What Capone doesn't realize is that Ness and the Prohibition agents aren't the only ones trying to take him down. For the past four years, another government agency with more manpower and resources than Ness has been going after the infamous kingpin: the Internal Revenue Service.

Tony Accardo have taken the reins of the criminal empire built by their mentor Al Capone. Thanks to Sam Giancana's takeover of the policy racket, the gangsters are now making millions. With so much money coming in, Accardo knows they need a place to hide it. They find their answer in a growing city where gambling is now legal: Las Vegas. However, the New York mafia is already there, led by criminal mastermind Meyer Lansky.

After becoming the most powerful mob boss in the country, Al Capone now finds himself locked up in America's newest and harshest maximum security prison: Alcatraz. Prohibition has recently been repealed and one of the Outfit's most important sources of income dries up.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. 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. Acardo 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... But new problems start to appear.

The story of America's most notorious gangster, Al Capone, starts on the streets of Brooklyn. In 1913, at the age of 14, Capone starts running errands for local gangsters - just one of many immigrants struggling to survive. One day, young Al Capone gets caught in a police raid. He quickly grabs what money he can, evades police, and runs to the headquarters of mob boss Johnny Torrio. Torrio rewards Capone for his quick-thinking. When Torrio recognizes Capone's intelligence and drive, he takes him under his wing.