Roger Ebert reviews 'The Da Vinci Code' and makes a useful point:
Both contain accusations against the Catholic Church and its order of Opus Dei that would be scandalous if anyone of sound mind could possibly entertain them. I know there are people who believe Brown's fantasies about the Holy Grail, the descendants of Jesus, the Knights Templar, Opus Dei and the true story of Mary Magdalene. This has the advantage of distracting them from the theory that the Pentagon was not hit by an airplane.
Still, I'll be joining the "othercott". There is no point encouraging them.
And I have a suspicion that this movie will flop miserably. Tom Hanks is best as an actor who plays a version of ourselves. That is, he is very convincing as ana ctor, but the appeal is that he always seems to be our friend, and always makes us feel good about who we are, even when his character suffers. I don't think this role quite suits that talent; I don't think a mincing academic with a bad haircut, out to destroy an ancient faith, is going to make us feel too positive about ourselves.