BOOK REVIEW : Thomas’ Thriller: Mellow and Savvy : VOODOO, LTD., <i> by Ross Thomas,</i> Mysterious Press/Warner Books, $19.95. 282 pages

The very first sentence of the latest Ross Thomas mystery is not likely to end up in an anthology of famous first lines, but it gives a fair idea of the value- and status-conscious prose that propels “Voodoo, Ltd.” through the curves of a very fast track.

“The two-passenger car that raced through Malibu shortly after 5 a.m. on New Year’s Day at speeds exceeding 82 miles per hour,” writes Thomas, “was an almost new Mercedes-Benz 500SL with an out-the-door-price of $101,414.28.”

Thomas, a master of the elegant clockwork thriller, has turned out a knowing tale of murder and blackmail among the hyphenates of the contemporary entertainment industry: an actress named Ione Gamble who wants to direct, a media mogul named William A. C. Rice IV who is found dead in his $15-million Malibu “beach shack,” and an agent-manager-lawyer named Jack Broach whose financial integrity may be discerned in the fact that he hangs fake Daumier sketches in his office.

“Voodoo, Ltd.” is a stylish and savvy whodunit, and the twin mysteries of the book--Who killed Billy Rice? Who is blackmailing Ione Gamble?--are unraveled with the cool expertise of a practiced stage magician. The affair ends in a flurry of gunfire and the revelation of dark secrets, but the reader is not likely to be shocked to discover who did what to whom.

What makes the tale worth telling is the rogue’s gallery of freebooters who ultimately solve the mystery, rescue the damsel in distress and put a slug in the bad guy. Thomas gives us a gang of international adventurers who are 40-something or older, world-weary and more concerned with college tuition for their kids than with mixing a proper martini.

“Voodoo, Ltd. “ is actually Wudu Ltd. (as mispronounced by a mysterious client with a German accent), and Wudu Ltd. is Artie Wu and Quincy Durant, a endearing pair of under-the-table entrepreneurs who grew up together in a San Francisco orphanage, ran away with a traveling circus and ended up as the proprietors of a detective agency that bills itself as “a limited liability company that does for others what they cannot do for themselves.”

They are still spry enough to engage in gunplay and still hot-blooded enough to end up in bed with a beautiful woman, but somehow the two of them come across like an old married couple.

“Question: Why is a ride with you like an IRS audit?” nags Durant while Wu is at the wheel. “Answer: Because I know it will end in disaster.”

To carry off the caper, Wu and Durant assemble a team of operatives from back rooms, hotel bars and prison cells around the world. It’s very much a post-modern over-the-hill gang that jets into Southern California with a suitcase of cash, an improvised cover story and a false passport or two.

There’s Booth Stallings, a White House consultant on counterterrorism who, at the age of 60, “abandoned it all to go adventuring.” Maurice (Otherguy) Overby is “a journeyman confidence man by trade” who claims that his last gig in the Middle East had something to do with beefing up the security for King Hussein. And then there’s the beguiling Georgia Blue, a renegade Secret Service agent who just finished a prison sentence on a murder rap.

Thomas has written a smart book with a good take on what passes for the Malibu movie colony--after all, the author lives there--but he cannot seem to shake off the habit of using trademarks as a substitute for description or of quoting prices, often to the penny, of wristwatches, hotel rooms, black-market revolvers and car rentals. At one point, we are told that his characters have consumed exactly $73 worth of Kentucky Fried Chicken, and a few pages later they are wolfing down “$81.56 worth of Mandarin-style, MSG-free Chinese food.”

Only rarely does the author work himself up to a choice hard-boiled phrase: “If she were to increase the tension only slightly,” Thomas writes of Ione Gamble’s first encounter with her criminal defense lawyer, “he suspected it would taste like electricity must taste and feel like a death threat must feel.”

Still, “Voodoo, Ltd.” is very much a mystery for grown-ups. We’ve already seen thrillers about former ‘60s radicals who have reached middle age without mellowing out, but “Voodoo, Ltd.” skips a generation and features the adult child of a pair of ‘60s terrorists who now runs a bed-and-breakfast in Topanga Canyon.

“Voodoo, Ltd.” is given a certain resonance, a mellow and ironic aura, by the fact that Wu and Durant and the rest of them have done it all before and are doing it again only because the kids are enrolling at Princeton next fall.

“Aren’t we all just a bit past smart?” asks one of the charming rogues in “Voodoo, Ltd.,” and the same can be said of Ross Thomas and the book itself.