John Gardner knows that the Nazis still sell books but seems a bit uneasy about it—a dilemma he resolves by contriving to have it three ways at once. "The Werewolf Trace" … is simultaneously laden with detailed lore about the final days in Hitler's bunker, debunking of the excesses of an intelligence service obsessed with the eradication of nonexistent evil, and a ghost story as well. Even more astonishing, at least to the point where one turns the pages to see how on earth he is going to bring it all off, the book actually works.

"Werewolf" is the British code designation for a 9-year-old boy who may, or may not, have survived the last hours of the Third Reich and who just might be primed to become "Werewolf, the inheritor of the Reich, the next in line within the Nazi Apostolic succession." But even if that were...