DECEMBER 6, by Martin Cruz Smith (published in Britain as TOKYO STATION). Simon & Schuster: New York, 2002, 352 pp., $26 (cloth) THE MASTER OF RAIN, by Tom Bradby. Doubleday: New York, 2002, 452 pp., $24.95 (cloth)

Try to imagine, for a moment, if Rick Blaine, the hardened expat cafe owner portrayed by Humphrey Bogart in "Casablanca," were to be transplanted to Tokyo on the eve of World War II. In place of Bogey and his alcoholic mistress Madeleine LeBeau are American Harry Niles and a hard-nosed Japanese babe named Michiko. Czech freedom fighter Paul Henreid, on the run from the Nazis, is nowhere to be found, but Niles buys freedom for five Chinese by winning a bet with a rabid Japanese officer who was on the verge of decapitating them.

A shrewd fixer who is fluent in Japanese and able to work both sides of the street, Niles operates through chameleonlike tactics, having grown up as son of a Christian missionary on the rough-and-tumble streets of Asakusa, his survival skills honed by being regularly pounded senseless by Japanese playmates. As he plies his trade among diplomats, militarists, spies, industrialists and journalists, his cynical, hard outer shell conceals the same decent and principled interior that was Bogart's stock in trade in "Casablanca."

Oh yes, the plot. "December 6" is one of those stories where something that the reader knows has happened -- the Japanese attack on Pearl Harbor -- is tested against a hypothesis of something that may or may not have happened. Which in this case is how the attackers were tricked into failing to destroy the U.S. Navy oil facilities on Oahu -- an immense strategic failure on Japan's part, as wiping the facilities out would have set back the Americans a great deal more than sinking battleships in 11 meters of water.