THE DOG WHO KNEW TOO MUCH

Why mess with success? Dog-trainer/p.i. Rachel Alexander's second case is so much like her fine debut (This Dog for Hire, 1996) that she could sue herself for plagiarism. Again there's a mysterious death—this time t'ai chi instructor Lisa Jacobs's alleged suicide—witnessed only by the victim's dog; again the stricken survivors are looking for an explanation for the inexplicable (why would got-it-all Lisa leave a note saying, ``I'm sorry. Lisa,'' and take a header out her window?); again Rachel hits the mean streets accompanied by her pit bull Dash. ``You won't learn anything worthwhile about Lisa by asking questions,'' Lisa's mentor and former boss Avi Ashkenasi tells Rachel. ``You must walk in her shoes.'' So as Rachel sweats to figure out which of Lisa's friends and students would've been most unhinged by her plans to move to China—and sweats too at the t'ai chi studio, the swimming pool, and the gym where she goes to ask all the questions she shouldn't—she wears Lisa's perfume and bracelet as well as her shoes, carries her keys, and beds her lover, half-Chinese swim coach Paul Wilcox. But her attempts to isolate a prime suspect fail when the front-runner gets killed—just like last time—clearing the way for another ton of moondust and (a sad innovation) an abrupt and arbitrary climax. Rachel's fans are advised to sit out her case of second- novel blues and wait for next year. If you missed her first, though, you may want to check out the most helpful canine sleuth since Asta.