By Peter Debruge According To The variety If you think the American presidential election has been unpredictable, wait’ll you see how capricious things get at the Vatican when the cardinals assemble to choose a new pope in “Conclave.” Adapted from the Robert Harris novel by Edward Berger, who assumes a very different challenge after “All Quiet on the Western Front,” this thinking man’s thriller unfolds like a murder mystery behind the locked doors of the Domus Sanctae Marthae, where the College of Cardinals is cloistered, except no one suspects foul play in the previous pontiff’s death. Still, intrigues abound as the papabili — those considered next in line for the job, played by such formidable actors as Ralph Fiennes, Stanley Tucci and John Lithgow — pull whatever levers ...