I read John Le Carré’s classic spy novel Tinker, Tailor, Soldier, Spy a few months ago, and found it difficult but brilliant. (The same can be said of most of his books).
Back in 1979, the BBC made a highly regarded TV mini-series adapted very faithfully from the book, starring Alec “Ben Kenobi” Guinness as protagonist George Smiley. I was keen to see it, and to compare it with the book.