Nigel West has studied the recently revealed documents about Soviet espionage against the Western Allies during and after World War II and has for the first time painted the complete picture of how the Soviet Union stole the secrets of the atomic bomb. The investigations by the British, Canadian, and US Military counterintelligence services through the Venona intercepts are placed in proper context and made intelligible by a master espionage history writer. What is revealed is the extent of the penetration by the NKVD and KGB of the most secret technologies of the era and how the West protected itself. A new and revised edition.