Ex-U.S. Justice Department agent Cotton Malone is intrigued when he sees a purse snatcher fling himself from a Copenhagen tower to avoid capture, slitting his own throat on the way down for good measure. Further snooping introduces him to the medieval religious order of the Knights Templar and the fervid subculture searching for the Great Devise, an ancient Templar archive that supposedly disproves the Resurrection and demolishes traditional Christian dogma.