When a young American woman is sent to Rome to begin a life of service to the church, she encounters a darkness that causes her to question her own faith and uncovers a terrifying conspiracy that hopes to bring about the birth of evil incarnate. “The First Omen” stars Nell Tiger Free (“Servant”), Tawfeek Barhom (“Mary Magdalene”), Sonia Braga (“Kiss of the Spider Woman”), Ralph Ineson (“The Northman”), and Bill Nighy (“Living”).