The All-Asia Science Fiction and Horror Movie Congress is being held in Hong Kong--which means that the usual chaos at Marshall's Yellowthread Street Police Station is even more colorful than usual. For one thing, the jail is full to bursting with drunks, pranksters, and lunatics, all in sci-fi garb. (""It looks like a cross between Wonder Woman and The Incredible Hulk! Where do I put it?"") And put-upon Detective Inspector O'Yee is calling every well-connected low-life he knows, desperately trying to impress his wife and kids by getting tickets to the horror movie premieres. But, as always, it's Detective Chief Inspector Harry Feiffer who gets the really ugly stuff: someone dressed as a spaceman is terrorizLng the convention's hotel, incinerating workmen and cut-rate filmmakers alike with a fire-throwing ray gun. (The possible motives include self-sabotage by the hotel's owners.) So, in his customary antic fashion, Marshall bounces around from one subplot to the next (there's also some sleuthing slapstick in a computerized car-park), with a tone that shifts blithely from vaudeville to blackcomedy to grim horror to sharply-etched pathos. (Don't miss the marvelous cameo by the hotel's aged cocktail-lounge pianist: ""Now they're going to move me into the foyer and all I want to do is go home to England and die!"") True, the mystery aspect is again too murkily convoluted for satisfaction, and the jumpiness eventually slides into mannerism. But the best comic moments are hilarious--and if you've acquired the very-acquired taste for Yellowthread Street, this will not disappoint you.