For nearly 50 years, FBI director J. Edgar Hoover amassed secret files on America's most prominent figures, files he used to smear and control presidents and politicians. Frontline reveals how Hoover's own secret life left him open to blackmail by the Mafia and offers a startling new explanation why the FBI allowed the mob to operate unchallenged for over two decades. The American Mafia, it is asserted, had damaging evidence about Hoover's sex life and they knew about his homosexuality.