Joe Lucadello, an informant to the Corleone family, was an agent, and head of the Miami offices of the CIA, who originally enlisted in the Canadian Air Force under Billy Bishop in 1941. Before this, he served in the Civilian Conservation Corps with Michael Corleone in the 1930s. Fearing Benito Mussolini's rise to power, the two falsified pilot's licenses to join Bishop, but Michael's father tipped Bishop off, and Michael admitted the truth to avoid damaging Lucadello's chances. At some point during World War II, Lucadello lost an eye in a bombing in London and wore an eye patch, and later a glass eye. After World War II ended in 1945, Lucadello left the Air Force and became a CIA agent.
It was around this time that he began informing the Corleone family of the CIA doings and their plans. Lucadello only met with Michael Corleone several times, although they were not specifically for business. He was also the main assistant of CIA director Albert Soffet.
Lucadello and Michael met for business several times throughout the years. In 1959, Lucadello was assigned to take out Fidel Castro, president of Cuba. In 1962, after a Castro body double was killed in an unsuccessful assassination attempt, he was assigned to eliminate the assassin, Carmine Marino. Lucadello also informed Nick Geraci, an enemy of Michael Corleone, that Michael was planning to assassinate him. Michael did not discover who had betrayed him and despite the fierce attempt to locate Geraci, he never found him.
Joe Lucadello was called to testify at a congressional hearing on the presidential assassination in Washington. The night before he was set to testify he was found dead in his hotel room with an icepick penetrating his one good eye. It was ruled as suicide, despite the obviously suspicious circumstances. It was implied that the Corleone family or his own agency may have had something to do with his death out of fear for what he could have revealed in the congressional hearing.
Real life sources
Joe Lucadello is probably based on the real intelligence agent Frank Sturgis, born Frank Angelo Fiorini.