I don't really understand the book Angles&Demonds...

I know that the book is about a feud between the illuminati and the Vatican Church between religion and science from the first 17 chapters, but the book is written completely different than what the book The Davinci Code was written like. What should I expect from this book, that I would not find in The Davinci Code, is there as much code breaking with cryptixes? Is it more action oriented, can someone tell me what to expect?