Fun-loving cop-novelist Wambaugh (Finnegan's Week, 1993, etc.) centers his latest San Diego police procedural around the international America's Cup regatta off Mission Bay and, as ever, comes up with a taut tale larded with raunchy dialogue. Two stories intertwine to give Wambaugh plenty of rope for a sailboat suspenser set mostly on dry land. First come the adventures of redheaded Blaze Duvall, a call-girl masseuse who gets involved with snobby bachelor Ambrose Lutterworth Jr., a 63-year-old client who happens to be the Keeper of the Cup--now likely to go to the Australian sailing team, which clearly has the faster boats. Mother-haunted Ambrose loves the very costly Cup as if it were the Holy Grail and lures Blaze into helping him keep it: His plan is to wreck the swifter of the Aussie's two boats while it's in dry dock. Meanwhile, Blaze's speedballing buddy, street hooker Dawn Coyote, flees her pimp, Oliver Mantleberry, but not fast enough to avoid Oliver's knifeblade. When Dawn dies on Blaze's front walk and Blaze disappears, horny vice cop Letch Boggs and aging homicide detective Anne Zorn team up to nab the elusive Oliver. Mission Bay water cops Mick Fortney and his sidekick Leeds are seemingly meant to carry this tale, and they do come upon two bodies in the water (floaters), but their work on water or land has almost nothing to do with the plot's outcome--nor do they. Instead, these nonstop jokesters hang about bars where the Aussies blow off stress with booze and boasting. The author's descriptive powers get full play at last when the climax moves aboard a fabulous pleasure yacht. No dimming of Wambaugh's storytelling skills or flow of smut. But his cop raunch, while amusing, has begun to pale.