Back in the 1970s I read “Tinker, Tailor, Soldier, Spy” and it was a classic. (sidenote: having just watched Juliet, Naked in which the boyfriend complains because the girlfriend listened to the cd before he did - a similar situation occurred over this book...) Anyway, I’ve had this book hanging around since 1997 and never got beyond the first few pages. I wasn’t missing much. I didn’t care about any of the characters and the plot was lukewarm at best. It wasn’t even very funny, although some reviewers apparently found it so.
My last read was a chick lit spy novel and it was much more rewarding. And dare I say, better written?