I have a soft spot for Cold War spy novels set in the world of ballet, chess, or other cultural exchanges. The setting might be a theater in Leningrad during a tour by a Western ballet company, or a chess tournament in Reykjavik. It's a genteel, intellectual world that becomes a front for recruitment, defection, and passing secrets. The contrast between the high culture and the dirty business of espionage is delicious. Plus, it often involves non-professional spies—diplomats, artists, journalists—who get drawn into the game, which raises the stakes.