Cardinal Lamberto

In the film

Cardinal Lamberto is visited by Don Michael Corleone on the advice of Don Tommasino, an elderly Sicilian Mafia boss. Michael tells Lamberto about a swindle involving corrupt Vatican bank officials Frederick Keinszig, Licio Lucchesi, and Archbishop Gilday. During the meeting, Michael suffers a low blood sugar episode due to his diabetes, and Lamberto orders orange juice and candy bars. Michael initially resists but eventually breaks down in tears, confessing to ordering the murder of his brother Fredo twenty years earlier.

Lamberto tells Michael he deserves to suffer but absolves him and says he still has a chance for redemption. Upon the death of Pope Paul VI, Lamberto is elected pope, taking the name John Paul I. He calls for an investigation into the Vatican Bank and requests a meeting with Keinszig. Keinszig has left Rome with money and documents. Fearing exposure, Keinszig, Lucchesi, and Gilday plot to murder the pope. Gilday poisons the pontiff's tea, killing him in his sleep.

Inspiration

The character of Lamberto and the film's depiction of his murder are based on conspiracy theories surrounding the death of the real-life Pope John Paul I, Albino Luciani. Theories, such as those in David Yallop's 1984 book In God's Name, suggest Luciani was murdered because he planned reforms for the Vatican Bank amid the Banco Ambrosiano scandal. The purported equivalent of Keinszig, banker Roberto Calvi, was found hanging under Blackfriars Bridge in London under dubious circumstances.