Dan Brown’s blockbuster art history-cum-theological thriller "The Da Vinci Code" has spawned a few dozen nonfiction responses, from theological critiques to travel guides. It's also launched a new fiction category: the religious thriller, or more bluntly, books that are surfing the big wave caused by "The Da Vinci Code." These books are distinguished by their  mixture of art history, history of Christianity, European settings, villainous clerics, heresy, cryptography and/or symbolism, murder most icky, and secrets that could change the course of civilization.
At least three relatives in the "Da Vinci" religious thriller family have hit bestseller lists so far this year.
Here’s a an overview of the major  players, and a rating system. Since Brown's popular thriller birthed not only theological controversy but a movie, I am evaluating these books for Christian orthodoxy, movie adaptation potential, and page-turning quality, each on a scale from 1 to 4 as follows: 

Heretic Pyres rate how far the book departs from traditionally accepted doctrines about the life of Jesus, Mary Magdalene, or other teachings. 

Popcorn Buckets measure screen potential.

Pages rate storytelling quality.

"The Secret Supper" by Javier Sierra
The telegenic Sierra hosts “The Other Side of Reality,” a Spanish TV show devoted to secret history and the supernatural. Like "The Da Vinci Code," "The Secret Supper" uncovers a supposed dark side of Leonardo’s The Last Supper, which in the case of this novel, is said to contain a heretical visual riddle.Sierra has done his history homework, attested to by a glossary of actual historical figures who are characters in the novel. The narrator, a member of the Inquisition investigating Leonardo on suspicion of heresy, is a Renaissance-era wonk good at solving riddles. Sierra says the novel, first published in Spain in 2004, owes more to Umberto Eco’s "The Name of the Rose"--which mixes murder, monks, and enigmatic riddles--than to Brown. Add a little Geraldo Rivera, and he may be right.
Depicting corruption in the 15th century church is more historical than heretical. While pivotal, gnostic theology enters in relatively late in the narrative.
This comparatively short book (329 pages) offers tight focus on Leonardo. His paintings would make world-class set decoration. But the only woman character is relatively minor.
Marred by a plodding start.
"Labyrinth" by Kate Mosse
"Labyrinth" was a bestseller in Britain last summer. A literary writer, Mosse here turns her hand to creating two parallel worlds: the contemporary south of France, where an archeological dig uncovers mysterious evidence that is the remainder of the other part of the narrative. In the same location in the early 13th century, the Cathar heresy--Cathars were highly moral vegetarian celibates who believed the material world was evil--is about to be crushed by the orthodox Christianity of northern France. The book is a grail quest; medieval knights abound. But the adventure heroes are two women, medieval Alais and modern Alice, whose sweethearts are charming, morally turpid, physically brave men. Even the villains are women. Well-researched detail includes a smattering of Occitan, the early language of southern France.
Though many characters are heretics, the book is essentially about love and family rather than theology.
Dan Brown meets Indiana Jones, and this time Indy is a woman. Medieval costumes and exteriors in southern France are begging for a screenwriter. (If you're a woman, add a fourth bucket.)
 Beautifully written, subtle.
"The Last Templar" by Raymond Khoury
The post-prologue opening sentence must have captured immediate attention in New York: “At first, no one noticed the four horsemen as they emerged out of the darkness of Central Park.” What at first blush looks like apocalyptic terrorism turns out to be Templars, an order of medieval military monastics. Unriddling this are archaeologist Tess Chaykin and FBI agent and practicing Catholic Sean Reilly, who face a pair of diametrically opposed villains. Each is determined to find the legendary hidden treasure of the Templars before anyone else does.
A twist at the end brings things back into the faith fold.
 Sword-related murder in New York’s Metropolitan Museum of Art, a perfect monster storm on the waters of the eastern Mediterranean, secret revelations inside the Vatican, plus a bonus of intermittent scenes of 13th century monks, are intensely visual. Khoury is, not coincidentally, a screenwriter.
 Romantic tension and back story for the archaeologist and the FBI agent add human interest to lots of external action and locations.