Leonardo DiCaprio will star in the film adaptation of the 2008 book Legacy of Secrecy in which authors Lamar Waldron and Thom Hartmann rather conclusively establish that three mob bosses – Carlos Marcello, Santo Trafficante and Johnny Rosselli – were responsible for the assassination of President John F. Kennedy as reported by Terri Schwartz for MTV: "DiCaprio will play FBI informant Jack Van Laningham, who befriends the southern mafia leader, Carlos Marcello, a man the book fingers as the potential mastermind of the 1963 murder (he reportedly even confessed involvement)."
With regard to Marcello's confession to Laningham regarding the Kennedy assassination, in reviewing Legacy of Secrecy last year for the Herald Sun James Campbell wrote the following: "The strongest evidence the authors produce is Marcello's confession to an FBI informant in the 1980s. 'The FBI had managed to get an informant inside Marcello's cell and Marcello trusted this guy,' Waldron said. According to a 1985 memo quoted in the book, the informant told the FBI: 'On December 15, 1985, he (the informant) was in the company of Carlos Marcello and another inmate at the Federal Correctional Institute, Texarkana, Texas, engaged in conversation. Carlos Marcello discussed his intense dislike of former President John Kennedy as he often did. Unlike other such tirades against Kennedy, however, on this occasion Carlos Marcello said, referring to President Kennedy, 'Yeah, I had the son of bitch killed. I'm glad I did it. I'm sorry I couldn't have done it myself.'"
From the web site for Legacy of Secrecy: "Legacy of Secrecy details the secret attempts of Robert F. Kennedy and his aides to expose his brother's killers . . . . It shows how RFK continued his war against the Mafia by focusing increased attention on the Mafia bosses behind JFK's assassination, until his own murder. RFK's associates continued his quest, almost exposing the truth several times. But like a deadly, high-stakes chess game – at the height of the cold war – they were blocked each time by three Mafia chiefs and a handful of CIA operatives. Legacy details each step taken by mob bosses Carlos Marcello, Santo Trafficante, and Johnny Rosselli to hide their involvement in JFK's murder, and the tragic results that followed. The long shadow of secrecy surrounding both JFK's murder and the coup plan set the stage for the murder of Martin Luther King, ultimately driving two Presidents from office, and bringing about the murders of five Congressional witnesses in the mid-1970s."
Robert Blakey, a mob buster for Attorney General Robert F. Kennedy and the principal architect of the Racketeer Influenced and Corrupt Organizations Act, is the author of The Plot To Kill The President in which he too concludes that the Mafia assassinated JFK as reported by David Talbot for Salon: "Blakey would emerge as the Warren Report's most authoritative critic and a firm believer that Kennedy had died as the result of a conspiracy, masterminded by Marcello and his Mafia ally, Santo Trafficante, the Florida godfather who had been driven t of the lucrative Havana casino business by Castro and who had been recruited in the CIA plot to kill the Cuban leader."