John "Handsome Johnny" Roselli (born Filippo Sacco; July 4, 1905 – August 7, 1976), sometimes spelled Rosselli, was a mobster for the Chicago Outfit who helped that organization exert influence over Hollywood and the Las Vegas Strip.

Capone was holding a party that night at his headquarters, Metropole Hotel, where Johnny could briefly meet him and the Chicago Outfit's inner circle.

Roselli was tasked with working with the Los Angeles crime family, to monitor Capone's investments and facilitate cooperation between the LA and Chicago organizations.

The LA branch of the mafia was at the time under the leadership of Joseph Ardizzone, and Roselli worked closely with Ardizonne's underboss Jack Dragna.

[3] After the Cuban Revolution in January 1959, Fidel Castro closed down the casinos that the Mob operated in Cuba, and attempted to drive the mobsters out of the country.

According to the Family Jewels documents released in 2007, members of the American mafia were involved in CIA's attempts to assassinate Cuban leader Fidel Castro.

[10] The documents showed that, in September 1960, the CIA recruited Robert Maheu, an ex-FBI agent and aide to Howard Hughes in Las Vegas, to approach Roselli under the pretense of representing international corporations that wanted Castro dead due to lost gambling interests.

Soon after his acceptance, Roselli discovered an elaborate card-cheating operation run by one of his Las Vegas friends, Maurice Friedman, and asked for his cut.

[3] Scores of wealthy men, including millionaire Harry Karl, the husband of actress Debbie Reynolds, and actor Zeppo Marx, were bilked out of millions of dollars.

Giancana's murder supposedly prompted Roselli to permanently leave Los Angeles and Las Vegas for Miami, Florida.

[3] On August 7, 1976, ten days after his disappearance, Roselli's decomposing body was found by a fisherman in a 55-gallon steel fuel drum floating in Dumfoundling Bay near Miami, Florida.

[15] Federal investigators suggested he may have been killed by Chicago mobsters for keeping an unfair share of the mob's gambling interests in Las Vegas.

The contract was sanctioned by the Chicago Outfit's consigliere Anthony Accardo, because "Roselli was becoming a public source of embarrassment to La Cosa Nostra".

[20] Based on information in the book Ultimate Sacrifice by Lamar Waldron, the program asserted that Roselli was responsible for framing Abraham Bolden who was arrested the day before he was to appear before the Warren Commission.

[20] In 2010, Playboy magazine published an article by Hillel Levin in which Roselli was also implicated in the assassination by Robert "Tosh" Plumlee and James Files, an inmate within the Illinois Department of Corrections.

Roselli and gangster Sam Giancana and their involvement with the CIA are the focus of a 2024 Paramount+ docuseries "Mafia Spies" based on the book by Thomas Maier.