In 1942, Lawrence Pritchard Waterhouse—mathematical genius and young Captain in the U.S. Navy—is assigned to detachment 2702. It is an outfit so secret that only a handful of people know it exists, and some of those people have names like Churchill and Roosevelt. The mission of Waterhouse and Detachment 2702—commanded by Marine Raider Bobby Shaftoe-is to keep the Nazis ignorant of the fact that Allied Intelligence has cracked the enemy's fabled Enigma code. It is a game, a cryptographic chess match between Waterhouse and his German counterpart, translated into action by the gung-ho Shaftoe and his forces.