These are the first three of 3 trilogies about the British Secret Service: the next are Spy Hook/Spy Line/Spy Sinker and Faith/Hope/Charity.

They follow the career of Bernard Sampson, whose wife defects to Russia. The machinations, the bureaucracy and callousness of the Service are deeply depressing while at the same being compulsive reading. Len Deighton's style is full of dry British wit and grit!