A graduate of Britain’s top-secret Joint Services School for Linguistics, Douglas Boyd was posted to an RAF airbase in Berlin in 1958 to spy on the armed forces of Warsaw Pact countries. He was subsequently arrested and imprisoned in solitary confinement in Potsdam, where he was interrogated by the KGB. In this memoir, Boyd describes his work as a signals interceptor in Berlin, where he listened in on pilots flying over East Germany, and his encounters with key security personnel.