Ted Allbeury "The Seeds of Treason"

If this book had a birth-place, it was Berlin, at check-point Charlie. I had walked there from the offices of my German publishers, and as I stood watching I wondered, for no reason at all, what would happen if MI6's head of station in West Berlin fell in love with the wife of his opposite number in the KGB in East Berlin.How did they meet?
What did they have in common? Why and how did they fall in love? And finally, what the hell did they do about it?
The book I was planning at that time was on a different theme.
Philby and his friends were the last people to commit treason for ideological reasons. a misplaced faith in the Soviet Union.
Since then, defectors and traitors have committed treason for very different reasons. The old human vices of greed, revenge, sex and ambition. Even love. They don't admit this of course, but even the KGB men who defect do it more for a red mustang for democracy