In the midst of the popularity surrounding “The Da Vinci Code” arrives “The Last Templar,” by Raymond Khoury.

Currently listed as a bestseller on many charts, “Templar” is certainly latching onto the star power of Dan Brown’s clue-filled Christian history—or, at least, pseudo-history—lesson.

The prologue opens in a Latin Kingdom of Jerusalem in 1291 where a Templar ship sails away with an enigmatic chest on board.

By the first chapter, we’re in present day Manhattan. At a gala in the Metropolitan Museum of Art celebrating a “Treasures of the Vatican” exhibit, four horsemen, swords and all, emerge from Central Park to nab one of the previously unseen artifacts.

Caught in this mess is Tess Chaykin, a beautiful and brilliant archeologist—and a single mother to boot.

From an enclave in the Met, Tess watches in horror as one of the horsemen becomes transfixed on some sort of decoding device.

Using her detective skills, Tess discovers the stolen item is a multi-geared rotor encoder, a “cryptographic device that dates to the sixteenth century,” according to Khoury.

Along with the FBI agent—and good-looking bachelor—Sean Reilly, Tess attempts to piece together the mysteries behind this encoder.

Naturally, it turns out to be a trail that leads them around the globe to locales like the underwater depths of the Eastern Mediterranean.

On this treasure-trove chase, Khoury tries to spice up the flirtatious banter between Tess and Sean, but it is a simple fact that authors of thrilling page-turners cannot legitimately write romance. Thus, we’re left with clunkers like “[Tess] knew something was definitely going on between her and Reilly, and she liked what she felt.”

Besides the nausea-inducing romantic elements of “Templar,” Khoury’s prose is actually compelling.

He has fine-tuned the careful balance of suspense and historical raptness, and the story of the Templars becomes engaging.

Khoury even seems gleefully happy to revel in the mysteries surrounding the Templars. At one point he even has one of Chaykin’s co-workers quote Umberto Eco’s famous statement about the group, telling her that “a sure sign of a lunatic is that sooner or later, he brings up the Templars.”

Khoury also injects as much early Christian history as possible, name-dropping the Gnostic gospels discovered at Nag Hammadi every couple of pages.

As a centuries-old conspiracy begins to unfold, Khoury’s quick timing intensifies, pitting our two heroes in a race for the truth—and survival.

Another caveat to Khoury’s history-based “Templar” are the clichéd characters that come across even more one-dimensional when compared to the non-formulaic plotline.

Along with our brainy archeologist and hunky agent, there is William Vance, a former colleague of Tess’ with a personal vendetta against the church after the death of his wife and stillborn child.

Perhaps the most egregious offense is the presence of a shifty emissary from the Catholic Church named Monsignor De Angelis who may or may not a by-the-book villain—either “a man of God with a gun, or a gunman who’s found God.”

Yet, the story is still pretty interesting so long as it centers upon the code-cracking and historical backdrops. When Tess and Sean discover the true motives behind the Templar actions, the story really heats up, with multiple double-crosses and revelations to keep the reader guessing.

It’s easily imagine a big-screen version of “Templar,” perhaps with some mousy actress like Maggie Gyllenhaal as Tess and someone like Kiefer Sutherland as Sean.

Indeed, Khoury is a former screenwriter, and “Templar,” a true page-turner, could easily be translated into a very successful film—so long as Khoury goes light on the romance.

—Reviewer Jessica C. Coggins can be reached at jcoggins@fas.harvard.edu.

The Last Templar
By Raymond Khoury
Dutton Adult
Out Now