The Honourable Schoolboy by Shaun McKenna

In the aftermath of a devastating betrayal at the heart of British intelligence, a weary but resourceful agent is dispatched to Hong Kong and Southeast Asia to rebuild networks and unmask Soviet influence; drawn deeper into a world of corrupt officials, criminal underworlds and compromising relationships, his mission becomes a study in moral erosion and personal sacrifice as the ruthless game of Cold War espionage and a shadowy enemy exact a heavy, unforgiving toll.