After centuries of destruction, one unsuspecting woman stands at the center of a conspiracy that could change the world forever in this thriller from the New York Times bestselling author of The Last Templar . Portugal, 1705 . In the dungeons of a Templar castle, a dying old man bequeaths an ancient, half-burnt book to his young inquisitor. Keeping one step ahead of those who would kill to wrench the book's secret from his hands, the inquisitor turns his back on his calling and sets off on an impossible journey to complete the old man's quest.   Baghdad, 2003 . Hunting for a mysterious bioweapon scientist, an army unit discovers a concealed state-of-the-art lab where gruesome experiments have been carried out on men, women, and children. The scientist escapes, but a puzzling clue is left behind: a circular symbol of a snake feeding on its own tail.   As the power of the symbol comes to light, revealing centuries of destruction left in its wake, a woman desperate for answers holds the fate of the world in her hands...