I've heard for years that [a:John le Carré|1411964|John le Carré|https://images.gr-assets.com/authors/1606816199p2/1411964.jpg] was the best example of a writer whose spy novels were the most literary, and after reading [b:The Spy Who Came In from the Cold|19494|The Spy Who Came In from the Cold (George Smiley, #3)|John le Carré|https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/books/1327719782l/19494.SY75.jpg|1177001], I agree.
 The problem with this kind of book for me is me; I'm can't follow intricate plots. It's a failing. The kind of friend I'd give or recommend this book to would be the kind who's good at chess and understands philosophy. I'm not saying you need to be good at those to appreciate it, but it would help.
Excerpt:

 A man who lives a part, not to others but alone, is exposed to obvious psychological dangers. In itself, the practice of deception is not particularly exacting; it is a matter of experience, of professional expertise, it is a facility most of us can acquire. But while a confidence trickster, a play-actor or a gambler can return from his performance to the ranks of his admirers, the secret agent enjoys no such relief. For him, deception is first a matter of self-defense. He must protect himself not only from without but from within, and against the most natural of impulses: though he earn a fortune, his role may forbid him the purchase of a razor; though he be erudite, it can befall him to mumble nothing but banalities; though he be an affectionate husband and father, he must under all circumstances withhold himself from those in whom he should naturally confide.