1916. The Great War rages overseas, and the whole of Europe, Africa, and western Asia is falling to the Central Powers. To win a war that must be won, Teddy Roosevelt, once again the American president, turns to his top secret Black Chamber organization--and its cunning and deadly spy, Luz O'Malley Arostegui ... Luz poses as an anti-American Mexican revolutionary to get close--very close--to a German agent code-named Imperial Sword ... In the mountains of Saxony, concealed from allied eyes, the German Reich's plans for keeping the U.S. from entering the conflict are revealed: the deployment of a new diabolical weapon upon the shores of America.