Tinker. Tailor. Soldier. Spy. I know it's probably more realistic that government intelligence/espionage types work in offices, but it makes for a really boring spy movie. A few people left the theater halfway into the movie, and I really wanted to go with them! But I stuck it out for Colin Firth.
There's another adaptation that my dad likes better. The more recent one...all he has to say that's polite is, "Gary Oldman looks like a constipated owl." I watch it for Tom Hardy and Benedict Cumberbatch, since they work well together and have soothing voices.
GI -- I feel with you, there. Am not much of a filmgoer; but concluded decades ago -- after struggling thorough a couple of them -- that the spy novels by John Le Carre (the film T.T.S.S. adapted from one of those, with the same title) were not for me: I steer completely clear of them, and of films derived from them. They just struck me as too gratuitously complicated, and sometimes needlessly weird -- for instance, the Soviet equivalent and opposite number and adversary of the British spymaster Smiley, is called Karla, yet he's a man -- in this context, why?
All the wheels-within-wheels and mirrors-within-mirrors and double / triple / quadruple / quintuple-crossing: I just didn't find all that stuff -- or Le Carre's writing of it -- interesting enough, to be worth the mental labour needed to try to make sense of it.
Largely I expect, because of my being male and elderly, and no film buff: I sometimes have the impulse to ask, "Who is this Benedict Cumberbatch entity -- and what a weird name to have -- of whom you Earthlings speak so much?"