From the opening account of Washington and Moscow's race to grab the models, machines, drawings, and personnel from Hitler's V-2 missile program at the end of World War II to Sputnik and then to Neil Armstrong's moonwalk, this is an utterly engrossing book -- largely because of the two characters around whom the story unfolds, and because Cadbury has the material to tell it from the inside. Wernher von Braun, the whiz in Hitler's rocket program who managed to reach American lines in a series of adventures worthy of a John le Carré novel, was on one side. Sergei Korolyov, who only by a series of miracles survived the Kolyma gold mines, the worst of Stalin's gulag, led the Soviet countereffort. To an eerie extent, the battles they fought and the timing of the key turning points for each were often parallel. This was true until nearly the end, when, after a lifetime of anonymity, Korolyov died a near icon, and von Braun died under a cloud -- not only because of his earlier rank as an SS officer, but also because of his ambiguous role in Mittelwerk, the unspeakable hell where the V-2 was mass-produced.