Geoffrey Household - Lonely hunter

"Widely recognized as a classic work, it is mentioned among the ten best spy novels in the world." (Graeme Shimmin, author of A Lill in the Morning).

It's the 1930s: a professional hunter is traveling through an unnamed Central European country ruled by a cruel dictator. He wonders if he could infiltrate the dictator's inner camp undetected. He succeeds. He takes aim at his potential victim and is already thinking about pulling the trigger when security eavesdrops. He is captured, tortured and left to fend for himself, but the hunter manages to escape and in incredible agony make his way through enemy territory to the safety of his native England.
But the British government cannot protect him, because then it would seem that they approve of his actions. He must leave society behind and literally disappear from the face of the earth like a fox into its hole. The hunter became the hunted.
A classic thriller, a masterpiece of suspense. A stunning, profound portrayal of the appeal of violence, the psychology of survival and the call of the wild.

It was an immediate success upon its release. It was made into a film in 1976 starring Peter O'Toole; and nowadays, Benedict Cumberbatch is preparing to bring it back to the big screen as a producer and protagonist.