"It's a melter," says Cathy Langer, a buyer for Denver bookstore Tattered Cover. Though the store keeps buying books (they won't release numbers), "the piles keep melting away." (Related item: Read an excerpt from Da Vinci Code.)

A murder mystery set against a religious conspiracy theory involving Leonardo Da Vinci's paintings, Jesus, Mary Magdalene, their child and the Holy Grail, The Da Vinci Code mixes page-turning suspense with art history, architecture and religious history.

Doubleday president Stephen Rubin knew the book was special from page one: "We sent out 70 pages early on, and response was unanimous and rhapsodic," Rubin says. "We believe very firmly that if within our own organization there is a unanimity of feeling, why should it be different anywhere else?"

An almost unheard-of 10,000 galleys were printed, more than any of Brown's previous books had sold. And then Doubleday brought out its secret weapon: Brown himself.

"Dan Brown has a sort of magic," says Charlotte Abbott, Publishers Weekly book news editor. "He has a sort of aw-shucks humbleness even though reading his books make you feel really smart."

Says Brown: "I would love to say the book's success is due solely to the writing and storytelling, but I think people are reacting to the subject matter: ancient histories and codes. ... That's what is capturing people's imagination."

The enthusiasm is spreading. Sales took off immediately and remain strong. Six weeks ago, it debuted at No. 4 on USA TODAY's Best-Selling Books list. Now, it is No. 8. It has sold 454,000 copies and is in its ninth printing, says Rubin. Book clubs, big-box warehouses and online and independent stores all report strong sales.

The book also struck a chord in the way it hits the Catholic Church; it says the church pushed women out of power and demonized them while covering up the meaning of the Holy Grail. Sales of a conspiracy book mentioned in The Da Vinci Code—Holy Blood, Holy Grail— have doubled at Borders, says the chain's publicity director, Ann Binkley.

A lapsed Catholic, Binkley is not surprised in the spillover interest. She went straight to the Web site of the secret society featured in the book, Opus Dei, and is eagerly awaiting Brown's next book about Freemasons.

"I always believed there was something between Jesus and Mary Magdalene," Binkley says, "Now I'm convinced."