BOOK REVIEW : Reigning Cat and Dog in Murder Mystery : WISH YOU WERE HERE, <i> by Rita Mae Brown and Sneaky Pie Brown</i> . Bantam Books, $18.95, 256 pages

Rita Mae Brown’s agenda isn’t hidden, but it sure is mysterious. She’s capable of writing books like “Songs to a Handsome Woman” and that literary landmark, “Ruby Fruit Jungle,” but she obviously has neither the temperament nor the inclination to become any kind of morose successor to Radclyffe Hall. Brown is not even like Florence King, that quirky female genius who went from radical lesbianism in her earlier books to right-wing gun-slinging in her later ones.

And to throw in just one last literary reference, you remember that man who declared “a separate peace”? Well, it’s as if Rita Mae Brown has written and signed off on her own separate Declaration of Independence. She’ll write about lesbianism when she feels like it, or the Civil War when she feels like it, or take the time to write an excellent book on the Writing Life (“Starting From Scratch”), or in this case, just kick back and let her cat--Sneaky Pie Brown--write a murder mystery.

In a time and place where writers are gnawing their fingernails to the nub about reputation and money and careers and God only knows what else, this reckless behavior is both baffling and refreshing.

To get the clue on Sneaky Pie, or “Mrs. Murphy,” as she names herself, you have to go back in time to Rudyard Kipling, who let animals talk in his “Jungle Books,” and then back forward in time to the work of animal trainer Vicki Hearne, who knows for sure that animals are far smarter than humans. Mrs. Murphy is the pet tiger cat of a nice young woman named Harry, the postmistress of the town of Crozet, Va. Mrs. Murphy shares house and bed space with a nice Welsh corgi, Tee Tucker, and this amiable dog-and-cat team do everything they can to cheer up their owner, Harry, that nice woman who’s going through a hard divorce from a man named Fair, who’s not very “fair” at all.

The plot of this novel is rambunctious and wacky. A paving contractor gets a cemetery post card, and within a few days, ends up squished in his own cement mixer. A Yankee woman named Maude Bly Modena, who makes an extremely good living in a store that packs and ships parcels, gets a cemetery post card, and soon after ends up squashed by a train. The sheriff of Crozet is just dense enough that Harry-the-Postmistress decides to help him find the murderer. Of course, from Mrs. Murphy and Tee Tucker’s point of view, they’re the ones who do all the detecting.

There’s a much more serious subplot. The mayor’s daughter is getting married, but because the mayor’s son has earlier married a black woman and left town in disgrace, he’s not going to be invited. The mayor’s wife is a tiresome social climber and won’t allow it. Will justice be done? Will the son, and his lovely black wife be invited back home for a reconciliation? Yes ma’am , just as sure as that intrepid cat and dog will find out who squished the contractor in the cement mixer and who squashed the Yankee lady on the railroad track.

This carefree canvass is really just a place for Rita Mae Brown--who, remember, has declared independence from the rest of us--to air certain of her own views on the human, feline and canine condition. Harry-the-Postmistress has a best friend, who notices, while watching Harry and her almost-ex-husband, that he’s playing that favorite ex-husband-game, “Starve the Wife.” Do it long enough, the friend observes, and the wife will lose her nerve and courage. Since husbands don’t think wives do anything anyway, they won’t feel guilt about not paying alimony, just rage that somebody somewhere has stopped ironing their shirts.

On the subject of psychopaths, serial killers and the like, Harry’s cat and dog have many a philosophical discussion. When a “sick” human being is born, why not kill it off right away, weed out the litter, so to speak, so that adult human beings who are cracked to begin with won’t grow up to kill, kill and kill again? For that matter, why kill at all, unless for food? And while they’re on the subject, why are human beings so incredibly dumb? They can’t see, they can’t hear, they can’t smell anything at all. Mrs. Murphy and Tee Tucker wash their collective paws of the human race, and you can see, at some level, Rita Mae Brown does too. Independence is her great thing. And animals, and nature, and a few friends. Not a bad agenda, come to think of it.

Next: John Wilkes reviews “Language and Species” by Derek Bickerton (University of Chicago Press).