Le Carre's best novel by a long way and probably the best spy novel I've ever read. Having just re-read it after 20 years it stands the test of time as a great thriller and story that stays with you long after you've put the book down. The time-shifting takes a little getting used to on the first read, but persevere as it eventually knits together so well. If you only ever read one Le Carre, read this one.