Believed by many to have been a Soviet spy throughout his career in MI5.
Typical upperclass Englishman, son on clergyman. Left Oxford without degree and went to China where he supported self as businessman and journalist and associated with known communists and agents of the GRU. Joined MI5 in 1936, though he was not a promising candidate. Was head of CounterEsponiage against Soviets and then Head of Security. Ended up as Director-General of MI6 from 1956 to 1965. Retired and died under cloud of suspicion.