Wilhelm Oerter, a middling trading company clerk, becomes ""a spy by default"" for the Nazis thanks to his ""incredible talent for mediocrity and anonymity."" The unassuming, insular Bavarian -- a man with neither ambition nor convictions -- maintains his cover after the Armistice of 1918. When directed to penetrate the Orkney Islands, Wilhelm becomes Will Hartz, a listening post of an innkeeper stationed just right to pick up information about the British Home Fleet harbored at Scapa Flow. A stoic, he still has to combat ""isolation that. . .threatened to suffocate and engulf him."" He eventually marries a reformed prostitute and becomes both a good father and contented citizen in 1934. With a wireless -- and mixed emotions -- he begins to transmit tidbits culled from his drunkard father-in-law. The late-blooming deep plant is taken out of cold storage when he assists in the kidnapping of an anti-Nazi journalist. However, the moment of truth comes after the outbreak of war when 'Willum' sends a message to have the unguarded fleet torpedoed. . .and then frantically rescues many of the injured men. Although he's personally decorated by Hitler, he becomes wistful and resigned until he's reinducted and subsequently killed. This is a slow-gripping, ably-constructed tale about that most tragic of human conditions: irresolution. Deliberate, involving -- an agent unprovocateur worth debriefing.