From the Pulitzer Prize-winning author of The Dead Hand comes the riveting story of the CIA's most valuable spy in the Soviet Union and an evocative portrait of the agency's Moscow station, an outpost of daring espionage in the last years of the Cold War.

While getting into his car on the evening of February 16, 1978, the chief of the CIA's Moscow station was handed an envelope by an unknown Russian. Its contents stunned the Americans: details of top-secret Soviet research and development in military technology that was totally unknown to the United States.

From 1979 to 1985, Adolf Tolkachev, an engineer at a military research center, cracked open the secret Soviet military research establishment, using his access to hand over tens of thousands of pages of material about the latest advances in aviation technology, alerting the Americans to possible developments years in the future. He was one of the most productive and valuable spies ever to work for the United States in the four decades of global confrontation with the Soviet Union. Tolkachev took enormous personal risks, but so did his CIA handlers. Moscow station was a dangerous posting to the KGB's backyard. The CIA had long struggled to recruit and run agents in Moscow, and Tolkachev became a singular breakthrough. With hidden cameras and secret codes, and in face-to-face meetings with CIA case officers in parks and on street corners, Tolkachev and the CIA worked to elude the feared KGB.

Drawing on previously secret documents obtained from the CIA, as well as interviews with participants, Hoffman reveals how the depredations of the Soviet state motivated one man to master the craft of spying against his own nation until he was betrayed to the KGB by a disgruntled former CIA trainee. No one has ever told this story before in such detail, and Hoffman's deep knowledge of spycraft, the Cold War, and military technology makes him uniquely qualified to bring listeners this real-life espionage thriller.