Donald Maclean was a British diplomat who spied for the Soviet Union in the Second World War and beyond. He was recruited as a "straight penetration agent" (not a double agent) while an undergraduate at Cambridge by the Soviet intelligence service. His actions are thought to have contributed to the 1948 Soviet blockade of Berlin and the onset of the Korean War. As a reward for his espionage activities, Maclean was brevetted as a colonel in the Soviet KGB.
10 best: Russian Spy Melita Norwood She was the seemingly innocuous assistant to the director of one of Britain’s atomic research centres, who coolly passed the secrets of the atom bomb to Russia for 37 years, before finally being identified in