The only surprise in this latest installment of the annual anthology is that two major talents--Lawrence Block and Robert Barnard--do not provide entertaining standouts. Block's entry is a coy, wispy little tale of wife-swapping between two vacationing couples in Europe--with a very pale bit of payoff irony. Barnard's is an unusually explicit, but oddly unconvincing, slice of sado-mashochistic psychopathology: an aging homosexual provokes a young hustler into escalating violence. Otherwise, it's a fair-to-middling sampling of US/UK formulas, thin on wit and style, with the two surest offerings coming from popular novelists new to the short-story form: B.M. Gill, sometimes verbose or overwrought in long fiction, is splendidly restrained and concise in ""A Certain Kind of Skill,"" a wry, stiff-upper-lip variation on the cuckold's revenge scenario; Sue Grafton's ""She Didn't Come Home"" is even more familiar in outline (a wife's disappearance), but distinguished by the bright detection/narration of California shamus Kinsey Millhone. There are locked-room puzzles from veteran Bill Pronzini (sleek and chatty) and newcomer David Braly (dim and corny). Josh Pachter offers another so-so case for Bahrain sleuth Mahboob Chaudri. Tales of revenge by Clark Howard and Thomas Aldcock (another newcomer) are atmospheric but crude--with an unpleasant, medically dubious AIDS punchline in the Howard story. And while three more newcomers provide serviceable recyclings--underwater action from Doug Allyn, imitation Roald Dahl from Nell Lamburn, domestic melodrama (the year's Edgar-winning story) from Robert Sampson--the inevitable Hoch entry (post-WW II espionage in Germany) is limp and stilted. One of the weaker recent gatherings, filled out with the usual--and always welcome--appendices.