There are several scenes outside the realm of possibility. The movie eliminated the presence of the news anchor which I think humanized the story. They also removed the fact that the Carmelengo is the biological son of the deceased pope. As a final departure from the book is the rescue of the final kidnapped bishop. The other noticeable negative is the cinematography. It really looks like they strapped a camera to someone and told them to run through the streets of Rome. Most scenes are not in sharp focus and hard to watch. The movie is entertaining and I would recommend it for the casual viewer. Just don't expect the detailed and exciting story the book offers.