Ever wonder how things might have been different for Rick Blaine, the ostensibly selfish nightclub owner from Casablanca, had he lived in Japan during the 1940s, rather than Morocco? Martin Cruz Smith offers a reasonable scenario in December 6. This slickly plotted, exotically atmospheric thriller opens in Tokyo just a few days before bombs start raining on Pearl Harbor. There we meet roguish Harry Niles, the culturally conflicted son of religious missionaries and owner of the Happy Paris, a club known for its enigmatic jukebox jockey, Michiko, who also happens to be Harry's mistress. With war rumors rampant, Harry-distrusted by both U.S. and Japanese authorities-"was skipping town. Any sane person would." He has a seat waiting on what may be the final flight out to Hong Kong, and plans to escape from there to the States with a British diplomat's wife. But first, there are business and personal affairs to settle, not the least of which is an oil-tank con he's been running on the Imperial Navy-a desperate strategy to stop his beloved Japan from entering into self-destructive conflict with America. Harry also has to duck a sword-wielding military fanatic, who's seeking revenge for a long-ago incident that cost him honor, and bid sayonara to Michiko, a woman as scary as she is seductive. (Oh, well, at least they'll always have the Happy Paris.) This book memorably re-creates wartime Tokyo, with its pet beetles and mincing geishas and naive belief that "victory lies in a faith in victory." Yet it's Harry Niles-cynical on top, sentimental beneath-who really carries December 6, a novel as brilliantly convoluted and captivating as any Smith (Gorky Park, Havana Bay) has yet concocted