In 1954, Soviet KGB agent Nikolai Evgenievich Khokhlov was sent to Germany to assassinate the leader of an anti-communist group. Instead, he defected and surrendered to U.S. agents. Khokhlov was glad to share the Soviet Union's spy secrets with America, including the loaded cigarette case he was to use in the assassination. But the KGB did not forget him.
Khokhlov later testified before the U.S. Congress about Soviet intelligence activities and became something of a media star. His story inspired a four-part series in the Saturday Evening Post called “I Would Not Murder for the Soviets,” and in 1957 he published a memoir, In the Name of Conscience. That was also the same year the KGB made an attempt on his life. After giving a speech in Frankfurt, Khokhlov had been served a cup of coffee, which he wrote in his memoir “did not seem to me as good as usual.” Soon he felt tired, and a “strange weight oppressed” his heart and stomach. Khokhlov collapsed in a parking lot. He had been dosed with thallium, a slow-acting poison that causes considerable pain before killing its victim. Khokhlov was lucky, though, and ultimately recovered after weeks in the hospital. His poisoning had coincided with the successful launch of Sputnik, and he reflected upon this in his book. “I, too, was an exhibit of the achievements of Soviet science,” he wrote. “Totally bald, so disfigured by scars and spots that those who had known me did not at first recognize me, confined to a rigid diet, I was nevertheless also living proof that Soviet science, the science of killing, is not omnipotent.”
Khokhlov did settle in the U.S., at first studying at Duke University. That's where he met J.B. Rhine (previously at Neatorama), the founder of the Institute for Parapsychology in North Carolina. Something about Rhine's research spoke to Khokhlov, who knew of Soviet research into ESP and other parapsychological phenomena. Read about Khokhlov's extraordinary life at Atlas Obscura.