At Close Quarters by Gerald Seymour
From the author of Harry's Game - A Sunday Times '100 best crime novels and thrillers since 1945' pick
Peter Holt, a young diplomat, witnesses the horrific murder of his fiance and the British Ambassador within days of a new posting to the Soviet Union. The report of the murder lands on the desk of a British Intelligence officer who suspects Palestinian involvement, althought the Russians insist that it was not a terrorist attack.
The British government are determined to extract revenge and Holt is the only man able to identify the assassin. He is sent to the Lebanon and the perilous Beqa'a Valley, which serves as a stronghold for the most extreme guerilla groups. Unauthorised access to the valley is virtually impossible, and capture by the Syrian Army would result in torture and death. His only company is Noah Crane, an Israeli expert sniper, who acts as his mentor and guide. But when Syrian Intelligence learn of their presence, their cover is blown. And now it is too late to turn back.