From the #1 New York Times master of international thrillers comes the story of a hunt across the globe, pitting nation against nation, as ancient myths of a lost continent prove all too real.The execution of a Vatican archivist within the shadow of the Kremlin exposes a conspiracy going back three centuries--to the bloody era of the Russian Tsars. Before his murder, he manages to dispatch a coded message, a warning of a terrifying threat, one tied to a secret buried within the Golden Library of Tsars, a vast and treasured archive that had vanished into history.As combative forces race for the truth behind this death and alarming discovery, Sigma Force is summoned to aid in the search--not only for this missing trove of ancient books, but to follow a trail far into the Arctic, to search for the truth about a lost continent and a revelation that could ignite a global war. But Sigma Force has its own difficulties at home after an explosive attack on the National Mall--one aimed at the heart of their covert agency--has left them vulnerable and exposed.The growing conflict--both on Russian soil and deep in the Arctic--will reignite a centuries-old war between the newly resurgent Russian Orthodox Church and the Vatican, while sabers rattle across the nations of the Arctic Circle, threatening to turn those icy seas into a fiery conflagration.Facing enemies on all sides, it will be up to Commander Gray Pierce and Sigma Force to unravel a mystery going back millennia--and uncover the truth about a lost civilization and an arcane treasure that could save the planet...or destroy it.