Did the Nazis really try to kidnap the Duke of Windsor from Portugal in 1940? ""Most of it is documented historical fact,"" says Patterson (The Valhalla Exchange); but the feeling here is that a tiny historical footnote has been padded out into a trifling piece of painless romantic suspense. Skeptical SS General Walter Schellenberg is assigned to persuade the Duke (relaxing with Wallis in Estoril) to join the Nazis and rule after the invasion; if the Duke (mistakenly thought to be pro-Nazi) is uninterested, then Schellenberg is to kidnap him. But the doomed Berlin Jewish underground, led by restaurateur Max Winter, learns of this plot, and Max's American niece, singer Hannah, is dispatched to carry the secret to Portugal--whither she flees, after shooting several Nazis and being helped to escape by. . . Gen. Schellenberg (!), who is a nice Nazi and very attracted to Hannah. So it's off to Paris, Spain, then Portugal, with Hannah being both trailed and protected by the Nazi general. And once they're all in the Duke's neighborhood, Schellenberg and a U.S. barkeep (shamelessly modeled on Bogart in Casablanca) do their best to frustrate a Nazi-Spanish attempt to kidnap the Duke, who finally gets Hannah's message while touring a bull farm. That's it, except for one final twist: the Duke says, ""My God, Wallis, wouldn't it be marvelous if I could play these bastards at their own game and beat them?""--and so he pretends to make a deal with the Nazis, learns the date of the planned invasion of Britain, and thus helps to win the war! Rather dubious pseudo-history--with cardboard characters (the Duke and Duchess especially) and some wretched dialogue (""So it's curtains for that damn Jew, Winter,"" says Heydrich). But it moves along quickly, with less gore and vileness than most Nazi-era suspense--a safe, bland bet, especially for those with a passion for the late Duke.