Fiennes was in town with actress Maria Botto and the film's producers to promote the project, which opens in U.S. theaters on Feb. 19. It is to be screened at the Vatican on Thursday.
"Risen is the epic biblical story of the Resurrection [of Jesus Christ] and the weeks that followed, as seen through the eyes of an unbelieving Clavius [played by Fiennes,] a high-ranking Roman military tribune," a synopsis said.
"Clavius and his aide Lucius [played by Tom Felton] are instructed by Pontius Pilate to ensure Jesus' radical followers don't steal his body and claim resurrection. When the body goes missing within days, Clavius sets out on a mission to locate the missing body in order to disprove the rumors of a risen Messiah and prevent an uprising in Jerusalem."
Fiennes, 45, is best known for his work in the Oscar-winning movie Shakespeare in Love and TV shows FlashForward, Camelot and American Horror Story. He recently made headlines when he was cast as light-skinned, African-American pop star Michael Jackson in a British TV movie.