"On November 2nd, 1962, the Cuban Missile Crisis was winding down. It had been the absolute height of the Cold War; the event that brought the US and USSR closest to nuclear war. The crisis had in large part been mitigated due to the placement of an incredible CIA source within the Soviet GRU; Colonel Oleg Penkovsky. He provided accurate intelligence on missile placement in Cuba. The CIA went to great lengths to protect his identity, including giving the impression that the information was coming from multiple sources, not just one.
Penkovsky was ultimately undone by a mole within the British government. The mole reported that Janet Chisholm, the wife of a British intelligence officer working in Moscow, was also active in collection activities herself. The KGB surveilled Janet and witnessed her meeting with Penkovsky. He was arrested on October 22nd. Eleven days later he sent an emergency signal to his CIA handlers that an imminent Soviet surprise attack was about to commence. The CIA couldn’t afford to ignore this possibility and sent case officer Richard Jacobs to check the pre-arranged dead drop; a matchbox hidden behind a radiator in an apartment building on Pushkinskaya Street. The KGB was waiting. Immediately after taking this photograph they seized Jacobs. He was able to drop the matchbox through a slit in his overcoat pocket and kick it away from himself, for what little good it did.
Jacobs was quickly kicked out of country, and Penkovsky was soon executed for crimes against the state. One of the best moles the West ever had in Moscow lasted just eighteen months. Rumors persisted for years that Penkovsky was cremated alive, and footage of his death was shown to GRU trainees afterwards as a warning of what happened to spies.
Originally posted to r/spycraft101."