For half a century, the case of Isaiah Oggins, a 1920s New York intellectual brutally murdered in 1947 on Stalin's orders, remained hidden in the secret files of the KGB and the FBI—a footnote buried in the rubble of the Cold War. Then, in 1992, it surfaced briefly, when Boris Yeltsin handed over a deeply censored dossier to the White House. *The Lost Spy* at last reveals the truth: Oggins was one of the first Americans to spy for the Soviets.Based on six years of international sleuthing, *The Lost Spy* traces Oggins's rise in beguiling detail—a brilliant Columbia University graduate sent to run a safe house in Berlin and spy on the Romanovs in Paris and the Japanese in Manchuria—and his fall: death by poisoning in a KGB laboratory. As harrowing as *Darkness at Noon* and as tragic as *Dr. Zhivago, The Lost Spy* is one of the great nonfiction detective stories of our time.