WMG / The Da Vinci Code

Dan Brown is a genius troll.

Consider that: he studied art history, so he can't possibly fail basic knowledge of it.Jacques Chirac was somehow involved in the movie's production (he, amongst other things, wanted Sophie Marseau, his daughter's friend, to play something there) and at least five of his ministers were freemasons - it's pretty likely that he's a mason as well (Mitteran being a mason in the book is likely a reference). The book has that general idea of marginalization of the church, which is what masons would very much adore. So there just might be quite some mason money involved in the book, and certainly in the movie.

Dan Brown himself is more of a Christian than a mason.

a) Everyone remembers the ending, right? The main antichristian in the book is suddenly the main evil guy as well.

b) There's so many blatant errors obvious for everyone who's a little bit intellectual, enough for them to disregard the theory altogether.

TL;DR: Brown took masons' money and wrote a book that mocks them.

Leonardo da Vinci, a supposed Grandmaster of an Order founded by Templars, is also affiliated with the Assassins.

And had a special relationship with one of them. Leonardo might've been a Double Agent to both.

The Tomb of Mary Magdalene beneath the Louvre contained a Piece of Eden.

In the movie version, Langdon is still in a relationship with Sophie at the time of Angels and Demons

In the books, Langdon had a fling with Vittoria Vetra, which didn't last (at the beginning of the The Da Vinci Code book, he's mentioned to never having seen her again after his time in Rome), and later met Sophie Neveu.

The movies switch the order of the two stories, and completely remove the romance between Langdon and Vittoria.

Now, the explanation for that is, that Movie!Langdon is still in a happy, committed relationship with Sophie by the time Angels and Demons happens.

the Catholic Church had a hand in making the movie and they make money from it

Any Christian/theologian/Art historian worth their salt would know that everything in the book/movie is bullshit so it doesn't actually threaten the image of the Catholic church. However, people who are against the church on principle would by the book/movie because the church condemned it. There is also a faction of Christians who would buy the book/movie just to burn it, keep it off the shelves etc. Finally there are people who will read the books and have an interest in going to see the locations thereby increasing the attraction of churches for tourists. So the church makes money from people who hate Catholicism, people who love Catholicism and people who buy what's in the book and want to visit Catholic churches.

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