"A richly detailed work...thought provoking."
- Publishers Weekly
"Greenspan sheds new light on the character, family, and motives of the notorious spy who gave the Soviet Union a blueprint for the atomic bomb. Klaus Fuchs’s espionage and its consequences raise timely questions about blind devotion to an ideology.”
—Cynthia C. Kelly, President, Atomic Heritage Foundation
“A riveting read. Greenspan skillfully and with nuance describes how one of the Manhattan Project’s prominent physicists, led to Communism by early struggles against Nazism, eventually became a important spy for the Russians. A tale of intrigue, competing moralities and human fallibility.”
—Gino Segré, author of The Pope of Physics and Ordinary Geniuses
"The Soviets had more than a half dozen spies inside the Manhattan Project, but none was more important than Fuchs. Greenspan takes us through the evidence with assurance. Most impressive is her detailed exposition of the strengths and weaknesses of MI5's investigations of Fuchs in the 1930s and 1940s, as well as Fuchs's evolution from German Social Democrat to devoted communist under the impact of Hitler's rise to power. "
--John Earl Hayes, coauthor of Spies: The Rise and Fall of the KGB in America