Conclave begins with the image of a cardinal tensely making his way along a Roman highway late at night, his crimson biretta cap clasped tightly in his hand. It’s a stark, almost funny image, the elegant robes of this high priest trudging through a bleak, contemporary urban setting. The characters of Conclave won’t spend much time in the world at large — this is one of the few times we will see one outside in Edward Berger’s film — but the dissonance will continue to resonate. These are men carrying out what they view as an ancient function: electing a new Pope, now that the old one has died. They diligently shut out the modern world, but it’s still there, outside the windows and beyond the doors, constantly felt in everything they do.

At the center of the squall is Thomas Lawrence (Ralph Fiennes), the dean of the College of Cardinals, whose job it is to run the conclave, as cardinals from around the world gather inside the hallowed sanctuary of the Sistine Chapel to cast ballots for a new pontiff. It’s a perfect role for Fiennes, who can do both placidity and intensity — sometimes, somehow, all at once. Thomas exudes gentleness and tolerance. He’s a deeply conflicted man who admits, in an initial address to the conclave, that he values doubt and abhors certainty — and yet, as the picture proceeds, he becomes more obsessed with controlling the outcome.

Berger’s film is adapted, quite faithfully, from Robert Harris’s 2016 novel, and it combines the pulp velocity of a great airport read with the gravitas of high drama. It solemnly depicts the ornate rituals around the death of the Pope — the ribbons placed across his door and fastened with melted red wax, the seals clipped off his rings, the constant prayers and the secretive mutterings — with only a slight nod to the sheer pointlessness of it all. It means something to these men, and that’s enough. Same, too, with the lugubrious dance of the conclave itself, with its round after round of balloting and tallying and quiet reflecting.

Many film critics who participate in year-end awards voting will find themselves nodding with recognition during Conclave at how allegiances shift between ballots in response to who’s ahead, who’s likely to win, and whose support seems to be crumbling. I have no idea how accurate this is to the way cardinals actually vote, but both the book and the movie have the confident ring of truth, or at least truthiness. And it’s interesting to learn that the Very Serious Men who elect popes scheme as effectively as the New York Film Critics Circle did when it voted (well-deserving) underdog Rachel Weisz best actress in 2012 to prevent front-runners Jessica Chastain and Jennifer Lawrence from getting the prize instead; or when the warring camps of Days of Heaven and Deer Hunter supporters at the National Society of Film Critics in 1978 famously fought each other to a standstill and allowed Bertrand Blier’s Get Out Your Handkerchiefs to sneak in and win Best Picture that year.

Where was I? Oh, right, Conclave. Amid such stately ceremony, Berger finds ways to insert gradually escalating tumult and cattiness. Though he tries to be fair and balanced, Thomas is allied with Aldo Bellini (Stanley Tucci), a progressive candidate who wants to continue the Church’s liberalization and engagement with the world. Opposing them is Goffredo Tedesco (Sergio Castellitto), a reactionary Italian who thinks the Church has been on the wrong track ever since it got rid of the Latin Mass in the 1960s. But there are other candidates as well — chiefly, Joseph Tremblay (John Lithgow), a supreme politician who, for all his outward soft-spoken humility, clearly has great ambitions. And then there’s Joshua Adeyemi (Lucian Msamati), a charismatic cardinal from Nigeria who could become the first Black pope.

None of these people actively campaign for the papacy. Save maybe for the flamboyant Tedesco (a not very big role that Castellitto turns into a full, rollicking meal), they’re all lowered eyebrows and hushed whispers and collegial exchanges, soberly prostrating themselves before God and seeking His guidance…all the while quietly and viciously stabbing each other in the back. Such muted machinations present a wonderful showcase for these actors, as well as Isabella Rossellini, as a head nun who becomes more central to the plot, and the relatively unknown Mexican actor Carlos Diehz, as a heretofore unknown cardinal named Vincent Benitez. Secretly named the Archbishop of Kabul, Benitez shows up unannounced on the day of the conclave and sends what promised to be a predictable gathering into the first of its many entertaining tailspins.

Despite the fact that they’ve all been cocooned deep inside the Vatican, with the doors barred, the priests of Conclave are all quite aware of how everything they do will have real-world repercussions, particularly in the way the Church is perceived. That fragile isolation isn’t just a psychological element. We sense throughout that the outside world is undergoing turmoil of which these men are mostly unaware — though we suspect they soon will be, both metaphorically and physically. Berger expertly milks that anticipation, then nails several artfully heated and lively climaxes. My audience at the Telluride Film Festival began roaring with delight and surprise, and I’ve heard similar reports out of Toronto screenings as well. So, well, don’t be surprised if this sinfully entertaining movie wins a few awards.