While investigating the murder of an American missionary in Ethiopia, young State Department lawyer Jaqueline Quartermane stumbles upon a magical word square in an underground church that guards the tomb of the biblical Adam. Drawn into a web of esoteric intrigue, she becomes the target of an elusive Pakistani opium kingpin who intends to convince the world that he is the Mahdi, the long-awaited Muslim Messiah of the Apocalypse. Her evangelical faith is tested when she thrown together with a roguish antiquities thief named Elymas, a Jewish atheist. This unlikely duo must race the Mahdi impostor to find the Thirteen Treasures of the Holy of Holies needed to resurrect Solomon's Temple. A trail of cabalistic clues leads them to the catacombs of Rome, the crypt below Chartres Cathedral, a Masonic shaft in Nova Scotia, a Portuguese shipwreck off Sumatra, and the caverns under the Temple Mount in Jerusalem. Intertwined with this modern mystery-thriller, a parallel duel is waged: The year is 1452. One of the most secretive societies in history, Portugal's Order of Christ, is led by a reclusive visionary, Prince Henry the Navigator. His medieval combination of NASA and the CIA schemes to foil its archenemies, the Inquisitor Torquemada and Queen Isabella of Castile, who plan to bring back Christ for the Last Judgment by ridding the world of Jews, heretics, and unbelievers. Separated by half a millennium, two conspiracies to usher in the Tribulations of the Book of Revelation dovetail in this fast-paced thriller to expose the world's most explosive secret: The true identities of Christopher Columbus and those now trying to spark the End of Days.