The Valley of the Fox — Joseph Hone

Driven from his home, a former spy disappears into the wildernessAfter decades in the British Intelligence, Peter Marlow no longer has the heart for conflict. He retires to the countryside with his second wife, Laura, and her daughter, Clare, an eleven-year-old autistic girl who reminds Peter what he spent all those years fighting for. But Peter’s past is not through with him—a killer has come to seek revenge for a long-forgotten feud. His bullet misses Peter but strikes Laura, destroying in an instant what had taken Peter a lifetime to build. With Clare in tow, Peter disappears into the woods, going underground while he plans his revenge. Armed only with a bow, camouflage, and his knowledge of the surrounding woods, Peter prepares to confront his old enemy. Although he’s lost his appetite for espionage, he will risk everything to protect Clare.  The Valley of the Fox is the fourth book in the Peter Marlow Mystery series, which also includes The Private Sector and The Sixth Directorate.