Fey Weldon is one of the last writer being in contact with secret services. After her studies at St Andrews in the 50's she got a job at the Search Information Department which was funded by M16 of the secret services. She has stated about that "my role was rather insignificant".
Ian Flemming, had a more safe life than his creation James Bond. He was an admiral assistant in the matters of sea spying. He soon was incharge of a sabotage at some romanian facilities, which was a failure. The perfect conspiracy was without a doubt in his novels.
John Bingham, a thriller writer (like the "A fragment ofg fear"). One of his staff members was David Cornwell, who started to write with the nickname John Le Carre when he was in Hamburg. His heroe , John Smily, is based on Bingham. Though Bingham accused David about spreading the idea that everybody who works at a secret service agency are "stupid and gay.."
Graham Greene published his book "The power and the Glory" in 1940, with many reveals the time when he was in the V section in Saint Albans.
A little more safe jobs had the poets Edmumd Spencer, John Milton, Andrew Marvel. Spencer carried letters from France and wrote propagnda texts about Irland, in the 1598 revolution.