The plot centers on the Papal conclave, 1458, which took place five years after the fall of Constantinople to the Ottoman Empire. The story material was sourced from a diary written by Silvius Aeneas Piccolomini, the only cardinal to ever record the secret proceedings of a papal conclave. The Conclave hinges on the drama surrounding a 27-year-old Spaniard, Cardinal Rodrigo Borgia (later Pope Alexander VI) as he struggles to save both his career and his life.