When a pope dies, cardinals younger than 80 gather at the Vatican to elect his successor in what is known as a conclave. Recent papal elections have offered glimpses of this highly secretive process by allowing television cameras to capture some of the pomp and prayers leading up to the voting.

But the world is left hanging the moment a Vatican official solemnly proclaims, “Extra omnes,” Latin for “all out,” and shoos everyone else from the Sistine Chapel before dramatically shutting its immense wooden doors so that the cardinals can begin selecting the next pope.

Edward Berger’s new drama, “Conclave,” which opens Friday, catapults audiences back inside the Sistine Chapel for a cinematically rare, if fictionalized, peek at the confidential electoral proceedings of the Roman Catholic Church.

Re“Ancient rituals clashing with modernity,” Berger said, describing the film in a video interview.

The film stars Ralph Fiennes as Lawrence, dean of the College of Cardinals, who in the film is responsible for leading the papal election, and Stanley Tucci, John Lithgow, Lucian Msamati and Sergio Castellitto as papal contenders. They are not based on real people but are instead amalgams of contrasting blocs within the church, traditionalist and progressive, that loosely define existing currents. “It’s all politics in the end,” said Robert Harris, who wrote the 2016 novel on which Peter Straughan based his screenplay.

“Conclave” is hardly the first film to involve a papal election, and church-based mystery-thrillers, like Dan Brown’s “Angels & Demons” or Raymond Khoury’s “The Last Templar,” have regularly made best-seller lists.