An inspiring book, The Da Vinci Code demonstrates that it's quite possible to for a best-seller to be ineptly written and clumsily plotted.

Aunt Tonnie sort of liked this -- though she says Angels and Demons was better. It's a publishing phenomenon. I thought I'd give it a try.

I enjoy thrillers. In this case, most unusually for me, I was consistently a step or two ahead of the game throughout most of the book. I solved the puzzles before the handsome Harvard professor, I saw the codes before the Cute Cryptographer.

Brown leaves some disturbing holes. Our heroes, for example, bamboozle a suspicious young London kid who is sweeping up a historic church that's supposed to be closed to the public. They claim to be Mr. and Mrs. Christopher Wren III, grandchildren of a man said to be a benefactor of that church. Surely a surly London kid would be a bit surprised that Mr. Christopher Wren III speaks American, and that his wife has a Parisian accent? If you're inventing a fake name in a London church, surely few could be less plausible.

Later, the London police try to arrest a suspect; the police charge into the room with guns drawn -- guns that British police seldom carry.

The book opens with our hero, a Harvard professor, who is staying at the Ritz after his lecture at American University of Paris. AUP is a very fine and generous institution, but when I spoke there, the Ritz didn't come up. Professor Langdon seems strikingly unbookish and worries remarkably little about his professional standing, his students, and his schedules. Cryptographer Sophie Neveu seems remarkably comfortable without her laptop and without her job -- and, it seems to me, an elite 20-something Parisian girl would not turn her life upside down and disown her beloved grandfather after discovering him in the middle of an apparent orgy. I'm told they order these things better than that in France.

A crucial and oft-repeated clue is a poem that instructs the heroes to seek "an orb that ought be on his tomb". Google finds about 56,000 "ought be's" and about 7,750,000 "ought to be's" -- I think the author dropped a word to make a bad poem seem archaic. ("Should be" would scan as well and makes just as much sense)

The real puzzle to The Da Vinci Code is, why has this rather clumsy and unspectacular book been so successful? It's only barely an adequate thriller. The art historical tie-ins and the bits of tourism are nice, but not especially original. The religious angle -- the mix of anti-Catholicism and Catholic sympathy and neo-early-Christanity -- might attract some fundamentalist readers, but surely there are sectarian minefields aplenty here.