If the throngs that packed a lecture at Brigham Young University on Wednesday night are any indication, Utahns are as taken with a best-selling novel about secret societies, cryptic messages and the relationship between Mary Magdalene and Jesus Christ as the rest of the country. And their interest may have as much to do with knowledge — or lack of — regarding their own faith traditions as it does with the twists and turns of the book's story line.

"The Da Vinci Code," by Dan Brown, has stayed atop the New York Times' best-seller list for months, selling more than 4.5 million copies since its release last March. More than a simple murder mystery, the book has been touted by some critics — and the masses who have devoured it — as a fascinating blend of fact and fiction, packaged with enough conspiracy theories that some readers who know tidbits about Christian history wonder if Brown has uncovered long-hidden truths.

The book has become so popular that filmmaker Ron Howard is making a movie of "The Da Vinci Code" for Sony Pictures Entertainment, expected to be released in 2005.

In an attempt to help local readers ferret out Brown's intermingling of historical figures and facts as the foundation for the book's fictional details and subplots, the BYU Museum of Art is hosting a series of four lectures titled "The Da Vinci Code: Mystery, Metaphor and Meaning, LDS Perspectives on The Da Vinci Code."

The first, given Wednesday by Eric Huntsman, an assistant professor of ancient scripture at BYU, drew such a large crowd that organizers had to close the doors to the museum 10 minutes before the lecture began, leaving hundreds of people outside. All 700-plus seats were filled.

Cheryl May, the lecture series organizer, said it had not been organized to promote the book but rather to build interest in an art exhibit to open at the museum in April. Museum officials have fielded numerous inquiries about questions raised in the book, whose premise is that Leonardo da Vinci left clues to the secrets surrounding the Holy Grail — which Brown identifies as Mary Magdalene — in some of his most famous paintings, including the "Mona Lisa" and "The Last Supper."

Several renowned scholars across the country have spent months quelling some of the conspiracy theories outlined in the book, and Huntsman's lecture addressed Mary Magdalene's relationship to Jesus Christ. The notion that the two were married or had an intimate relationship was debated for centuries and had been debunked among the majority of Christian historians.

But ancient texts discovered and translated within the past century — including the "Gnostic gospels" named after Christ's disciples including Thomas, Philip and Mary — have rekindled debate not only about Mary's relationship with Christ and her life after his death, but whether he told her information before his Crucifixion that had been withheld from his apostles. Much of the book's conjecture about Mary comes from such noncanonical texts, including the "Gospel of Mary."