The early years of the Cold War found the United States struggling to compete in the espionage war against the Soviet Union. With no history of a peacetime intelligence service, the newly created U.S. Central Intelligence Agency lacked the experience for conducting high-level espionage against the USSR.

Viktor Neiman, a senior officer in the U.S. Department of State Bureau of Intelligence & Research, returns to Europe after serving in the wartime OSS. Teamed with an independent group of expatriate anti-Soviet Russians in Paris, Neiman's network makes a breakthrough espionage penetration of the Soviet foreign ministry and the Soviet nuclear weapons program during the winter of 1952-53.