Cambridge Five

The Cambridge Five was a ring of spies, recruited in part by Russian scout Arnold Deutsch in the United Kingdom, who passed information to the Soviet Union during World War II and at least into the early 1950s. Four members of the ring have been identified: Kim Philby (cryptonym: Stanley), Donald Duart Maclean (cryptonym: Homer), Guy Burgess (cryptonym: Hicks) and Anthony Blunt (cryptonym: Johnson); jointly they are known as the Cambridge Four.

Several people have been suspected of being the "fifth man" of the group; John Cairncross (cryptonym: Liszt) was identified as such by Oleg Gordievsky, though many others have also been accused of membership in the Cambridge ring.

The term "Cambridge" in the name Cambridge Five refers to the recruitment of the group during their education at Cambridge University in the 1930s. The four known members all attended the university, as did the alleged fifth man, Cairncross. Debate surrounds the exact timing of their recruitment by Soviet intelligence; Anthony Blunt claimed that they were not recruited as agents until they had graduated. Blunt, a Fellow of Trinity College, was several years older than Burgess, Maclean, and Philby; he acted as a talent-spotter and recruiter.

Both Blunt and Burgess were members of the Apostles, an exclusive and prestigious society based at Trinity and King's Colleges. John Cairncross, long suspected of having been the 'Fifth Man', and formally identified as a Soviet agent in 1990, was also an Apostle.

Other Apostles accused of having spied for the Soviets include Michael Whitney Straight, Victor Rothschild and Guy Liddell.