“God’s Candidate”
Cardinal Angelo Scola, patriarch of Venice, celebrated a Mass to mark the 30th anniversary of the election of John Paul I, “the smiling Pope.” Cardinal Albino Luciani was elected Pope on August 26, 1978. Acclaimed for his refreshing candor, spontaneity and wit, he was described by Cardinal Basil Hume as “God’s candidate.” 
John Paul I was the first Pope to have a composite name, a gesture to honor his two predecessors - John XXIII and Paul VI.
The “smiling Pope” died on September 28, 1978, 33 days after his election to the papacy, allegedly of a heart attack.
Many people, myself included, believe he was murdered for changes he planned to implement in the Vatican.
Most conspiracy theorists believe John Paul I was the victime of a plot involving powerful men linked to the Mafia, the Vatican Bank, and P2, an illegal Masonic Lodge whose membership included senior Italian politicians. One of these men was Bishop Paul Marcinkus, then head of the Vatican Bank.
According to some investigators, John Paul I was murdered not only because he was planning to purge the Vatican Bank, but also because he was planning to demote or dismiss powerful figures in the Curia, the Vatica bureacracy.
There were several other rumors that may also have contributed to his assassination: the belief he was planning to proceed with the ordination of women; and continue to push the reforms of Vatican II, particularly with the bureacracy.
The late Cardinal Aloisio Lorscheider of Brazil, a strong supporter of John Paul I, decided to speak out 20 years later. He had to “record with sorrow” that the official version of John Paul I’ death was open to question. The cardinal noted that Cardinal Jean Villot, the then Secretary of State, had refused to allow a post mortem examination. 
“I have to say that a suspicion remains in our hearts,” Cardinal Lorscheider said.
Three well-known books about the death of Pope John Paul I include: In God’s Name by David Yallop; Murder in the Vatican by Lucien Gregoire; and A Thief in the Night: The Mysterious Death of Pope John Paul I by John Cornwell.