https://en.wikipedia.org/wiki/Kim_Philby
a British intelligence officer and a spy for the Soviet Union. In 1963, he was revealed to be a member of the Cambridge Five, a spy ring that had divulged British secrets to the Soviets during World War II and in the early stages of the Cold War. Of the five, Philby is believed to have been the most successful in providing secret information to the Soviets.[4]
Cambridge Five
