The Spy Who Came in from the Cold was the work of a wayward imagination brought to the end of its tether by political disgust and personal confusion. Fifty years on, I don't associate the book with anything that ever happened to me, save for one wordless encounter at London airport when a worn-out, middle-aged military kind of man in a stained raincoat slammed a handful of mixed foreign change on to the bar and in gritty Irish accents ordered himself as much Scotch as it would buy. In that moment, Alec Leamas was born. Or so my memory, not always a reliable informant, tells me.