I read on Wikipedia that John LeCarre actually was a spy for the British espionage unit M-16, and that his cover was blown and his career ended by double agent Kim Philby. Gerald, the Soviet double agent in the book, is to some extent a portrait of Kim Philby, and the protagonist George Smiley is “modelled on former Lincoln (College) rector Vivian H. H. Green.”
So the novel has some basis in fact and history. I thought it was a good book, but I did have some trouble following the plot. Between the British slang and the dated slang (published in 1974) and, most of all, the spy-talk, I was lost a good deal of the time. Then, too, I have the unfortunate habit of skimming over sections whenever I lose the thread of the story looking for a place to pick it up again. I often do this skimming unconsciously, and I sometimes skip right over the thread I needed to find.
So I may have missed a few details, but I got the gist of the story. George Smiley is an unwillingly retired M-16 agent who’s called back in to deal with a possible Soviet double agent entrenched in the highest echelons of M-16. The novel tells about how Smiley goes about finding the double agent, and it also deals with the lack of trust fostered by an environment whose stock in trade is betrayal. In Smiley/LeCarre’s M-16, no one fully trusts anyone, with good cause. I didn’t understand how Smiley knew exactly who to interview in order to figure who the Soviet “mole” was, but I suppose it was buried somewhere in the jargon.
So it’s a spy novel with a theme, trust and the lack of trust, and betrayal in politics and in realtionships. (Smiley’s wife, by the way, is cheating on him and has been for quite some time, a fact that is not without significance in the world of LeCarre’s spy story.) I read that there are two more novels by Le Carre featuring the retired spymaster, George Smiley. I probably won’t look for them anytime soon, but if you’re interested in a spy novel with a little more depth than James Bond, you might take a look at Tinker, Tailor, Soldier, Spy. Then ‘splain the nuances to me.