Notorious Russian Spies Throughout History

Kim Philby
In 1941 Philby joined the British intelligence, MI6, despite the fact that he had been working for the Soviet intelligence since 1933. MI6 only realized he was a double agent in 1963, leaving a 20-plus--year window for Philby, who reached the highest ranks of the British clandestine service, to hand over as much top-secret information as he could. Philby managed to escape to Moscow, where he lived out his remaining years as a hero of the Soviet Union. He died in 1988.

• Double Agents: A Photo Dossier