Agent 6 - Tom Rob Smith

Former Soviet Secret Service agent Leo Demidov has built himself a new life as a civilian with his wife Raisa, and their two teenage daughters, Elena and Zoya. The Soviet Union is a country trying to reassert itself after the murderous excesses of Stalin and the chaos of the following years, and as the Cold War continues powers inside Russia seek to topple their great enemy, the United States of America. Communist allies within the United States will prove vital players in this game of intrigue and revolution.
Raisa and their two daughters travel to the United States on a diplomatic mission, but a horrifying tragedy destroys everything Leo and Raisa have built. Leo must get to the States somehow and find out what happened. Exiled from the Soviet Union and separated from his family, Leo's quest takes him through the stark wilderness of Afghanistan, reawakening all his old instincts and forcing him to confront his demons. But whatever it costs, wherever he must go, he will find Agent 6.