Truth be told there was an outfit in WWII the Brits called SOE, I think. They were the last radio link in the chain defending Gibraltar. One of the agents manning the elaborate cave system was designated GB007. The Commander of the Fleet the SOE chaps were in communications with during the start of the invasion of North Africa was Ian Fleming ...
Do you wonder that Dr Julian Bashir in Deep Space 9 was so fascinated with spies? A quarter of the mystery shelves of my bookcases must be spy novels.