On a humid June morning in 1957, FBI agents swarmed a Brooklyn hotel room and addressed a mild-mannered artist as Colonel. He stared in silence for twenty minutes, then gave the name of a dead friend as a hidden distress signal to Moscow. This episode uncovers the man behind the alias, Soviet master spy William August Fisher.

Born in England to Russian revolutionaries, Fisher built a ghost life in America running an atomic spy network while posing as an aggressively ordinary Brooklyn artist. His flawless tradecraft was undone not by brilliant counterintelligence but by the simple human failings of his own deputy.

• He was fluent in English, Russian, German, Polish, and Yiddish and obsessed with building radio transmitters as a teenager
• He ran wartime radio deception operations before infiltrating the US in 1948 under stolen ...