I bought a copy of the Da Vinci Code for $7 in Vietnam. Had I known ahead of time what a crappy book it was I would have bartered him down to $3.50. It certainly wasn't worth $7.
I think Dan Brown did a lot of research, probably of dubious quality, and was so proud of how much research he did that he felt the need to put absolutely everything he found out in the book. It will be easy to cut it down to a 120 minute film, because they'll be able to cut out every single instance of the book flashing back to one of Langdon's irrelevant lectures.
I assume that most people on this thread have read the book, but here's a spoiler warning anyway.
People who do Crime Fiction for EE1 might know that as a murder mystery, it breaks one of the fundamental rules (and doesn't do it in a way that improves the book). Brown doesn't play fair with the reader- the investigators know things that are hidden from the reader. And he does it in the same way that a five year old teases a dog with a biscuit- 'I'm going to give it to you, oh wait, no I'm not, hahahaha' until I didn't care how the body was positioned, what Sophie saw her grandfather doing in the basement or what Aringarosa went to Rome to talk about six months ago. The clues are known to the investigators, but are only released to the reader line by line. I assume this is to give Langdon a head start, since his ability to solve codes is laughable. I solved most of them ages before the main characters did, and last time I checked I'm not a symbologist or trained cryptologist.
And if you're protecting something as important as the location of the Holy Grail, not to mention your precious wife and grandson, why oh why would one of the protective codes be as absurdly simple as backwards writing?
