Dark Star
Dark Star may be the most authentic espionage novel ever written. Set in the period of the Stalinist purges, it captures not only the intrigue and danger of clandestine life but the ennui, the bureaucratic infighting, the seediness of cheap rooms, the hasty moments of furtive sex, and the moral compromises of a life whose only goal becomes surviving a world where nothing is clear and betrayal is as common as death.