Ralph Fiennes manages ambition and deceit as the Catholic church picks a new pope in 'Conclave'

If fiction depicts reality, then the election of a pope can be cutthroat. At least that's how it's portrayed in the new movie Conclave.

In the opening scene, the pope is dead. His room is sealed. Cardinals from all over the world descend on The Vatican to sequester themselves until they've chosen the next one.

Ralph Fiennes plays Thomas Lawrence, dean of the college of cardinals. He's in charge of managing the vote – as well as the cardinals' strong and various opinions about the future of the church. They connive, strategize and uncover damning secrets during their deliberations.

"Cardinals, priests – they're human beings. They might have ambition," Fiennes told Morning Edition host A Martínez. "Where ambition becomes egocentric and self-serving is one thing; they might have ambition to do well in the church. I think it's okay to be ambitious for something."

Fiennes's Cardinal Lawrence claims not to want the papacy for himself, but he's allied with Cardinal Aldo Bellini (played by Stanley Tucci), a reform-minded American. Bellini lobbies for the job mostly to oppose an Italian Cardinal, Goffredo Tedesco (played by a scene-stealing Sergio Castellitto) who represents the conservative wing of Catholicism. His ambition is undeniable. Tedesco wants to take the church back to its pre-Vatican II days of Latin liturgies and unchallenged patriarchy.

"It's not just about stopping Tedesco," Fiennes explains. "It's also about advancing the church into issues of sexual orientation, gender, women – key liberal issues."

Ralph Fiennes grew up with his own experience in the Catholic church. "My mother was a committed Catholic," he says. He spent part of his youth in a Catholic boys school in Kilkenny, Ireland, "until I was about 13 when I rebelled. I said to my mother, 'I don't want to go to Mass anymore. I don't understand it. I don't feel it. I don't believe.'"

Still, the script for Conclave spoke to him. "I've always carried in my adult life a real curiosity about faith – and a real interest in people who are committed to a life in the church."

Fiennes researched his role by speaking with Vatican insiders. At first, he was sheepish about how the work would be received. "I met some priests who were incredibly helpful," he remembers. "They're thinking philosophically a lot about these big questions. I didn't meet anyone who I felt was locked in defensively in relation to 'Here's an actor playing a cardinal.' I felt I met open and kind people who said, 'Yes, these are challenges.' They are aware and sensitive to all kinds of things relating to the church's role. I found it quite inspirational."

Conclave opens in U.S. theaters nationwide on Friday, October 25.