I like conspiracy theories, and you can make great fiction by assuming they are true, as the X-files proved.

What bothers me about this book is firstly that it's not great fiction, it's pulp. The action is smeared out with easily digestable but cheesy details (I don't care how the hair of the heroine smells) and most of the suspense is created artificially by withholding information. For example, we're told early on that the heroine once saw something terrible, and over the next 200 pages we get bits and pieces of information about where and when she saw it and how much it shook her before we are finally told what the heck it was. In the first half of the book every chapter also ends with a lame cliffhanger like "and then he saw something amazing" after which the next chapter switches to another character. It's all very much like a dumb soap opera.

What is far worse than the awful style and structure though is that Dan Brown presents many aspects of the conspiracy theory as actual history that just doesn't happen to be common knowledge. The main character is an academic who regularly says things like "historians agree that" or "it is now commonly accepted among historians that" followed by some wild extrapolation of fabricated facts and speculations. Because of the amazing popularity of this book and the general naivity of people, millions must now believe that a lot of this crap is true. No wonder the Vatican is so pissed haha.

I'd give Dan Brown credit for coming up with this elaborate theory, but he just took it all from the 1982 book Holy Blood, Holy Grail written by three very imaginative 'historians' who understandably sued Brown for plagiarism. I've browsed through their book; it consists entirely of "it is possible that" followed by bits of speculation that are then assumed to be true and used as bases for further speculation.

For example, they say "it is possible that" Maria Magdalena was a descendant of the first Jewish king, Saul, because she was said to belong to the tribe of Benjamin from which Saul had come as well - that is the only basis for this speculation. Jesus on the other hand is considered to be a descendant of David just because the New Testament says so; never mind that everyone claiming to be the Messiah had to pretend being an heir of David because that's how the Old Testament prophecied it; and never mind that Mark and Luke fabricated two entirely different genealogies to demonstrate how Jesus descended from David.

By combining this wild speculation about Mary with this obvious fabrication about Jesus, their children now suddenly unite the lines of the two great Jewish kings and make Jesus and his family a major threat to all men of power in 1st century Israel, which is why Jesus was crucified and Mary had to flee. In the real world however, Jesus was such a completely unknown nobody that in the many surviving historical records (Jewish and Roman) of his time, he only gets one (1) brief mention. That Mary Magdalena came to France, of all places, is assumed because a French monk wrote so in the 7th century.

These are just the first two links of the long chain of assumptions that make up this ludicrous conspiracy theory. The funniest thing though is that the authors think that once the cat is let out of the bag, the people of Europe will welcome the current descendant of Jesus as a kind of priest-king to replace our democratic governments. This expectation speaks volumes about their grip on reality.

Anyway, the Da Vinci Code does have a lot of interesting information about the places and artifacts that feature in the story, so being offensive to the Vatican isn't its only quality. I suspect that the upcoming movie will be a lot better than the book though (it has a superb cast in any case), so if you haven't read it yet I recommend you wait for that.