In his autobiography, The Sport of Queens, Dick Francis could not be more direct about his latest profession: "When I write any one sentence. I think first of all of what I want to say. Then I think of a way of saying it." The brisk assessment of a situation, the lucid self-reliance, the smart refusal to fuss about what other people fuss a lot about—this confession rings with the elements of style for many a Dick Francis protagonist. Racing journalism was the means for Mr. Francis, in 1957 a retired Champion Jockey in Britain, not only to earn a different kind of living, but also to perfect professionally succinct prose conveying vivid action. Adept hero, dexterous prose—these are the unfailing aspects of Dick Francis' series of 31 novels.

With Driving Force he treats his readers to another amiably disillusioned, smart and un-self-pitying ex-jockey narrator. Freddie Croft's current business is transporting horses to English race tracks. "I had told the drivers never on any account to pick up a hitchhiker but of course one day they did, and by the time they reached my house he was dead." "Of course" nonchalantly removes this first sentence from any danger of seeming simply a mystery's obligatory hook.

The "multimillion fortunes on the hoof," as Freddie terms race horses, with their fragile legs and fractious moods, pose tricky problems in transit. Largely by computer, in pinches by intuition, Freddie choreographs the crisscrossing of England by his fleet of huge vans. Mr. Francis, who can turn the nuts and bolts of any profession to fictional gold, sketches a thriving business whose peculiar emergencies include claustrophobic horses, flu-stricken drivers and of course the occasional dead hitchhiker. But horses are fortunes to Freddie, investments to be protected rather than real, errant individuals, and whenever a Dick Francis hero strays too far from actual horseflesh, the novel he's in forfeits a great source of gusto.

My private theory is that horses function as the id, the unruly life force, for Mr. Francis' disciplined sleuths, and that cut off from horses these narrators have the brainy, controlled dryness of too much superego. (I know: this analysis would rate, from any Dick Francis hero, one of those infinitely ambiguous "Mm" s. Or worse, "Right," Brit for "in a pig's eye.") Irkab Athawa, a dazzling 3-year-old, steals those scenes he's in and, briefly, Freddie's heart; the horse could have figured more consistently in the plot as it complicates.

It gets very complicated. Beginning with that dead body, Freddie is confronted with a wicked scam, on the cutting edge in its technology and implications. His vans, he finds, have been transporting something other than horses. Driving Force is rich in information—about Cockney rhyming slang, the Michelangelo computer virus, intercontinental smuggling and ticks (yes, ticks), among other subjects. Mr. Francis deals with the potential for boredom in exposition, or at least flatness, by putting the more obscure explanations in the mouths of completely charming, completely obsessed eccentrics ("Guggenheim moved in this mysterious territory [his laboratory] with the certainty of a Rubik round his cube"), and I read merrily along, entranced. It's either hard or impossible to read Mr. Francis without growing pleased with your self: not only the thrill of vicarious competence imparted by the company of his heroes, but also the lore you collect as you go, feel like a field trip with the perfect guide.

Driving Force isn't flawless Dick Francis. Too many characters share the quirk of prefacing remarks with "Er." I wanted to kill Freddie the next time he responded to a remark with "Mm." Too many mouths hang open in astonishment. Successive one-sentence paragraphs seem an effort to trump up suspense that isn't coming naturally. Freddie's romance with an undercover agent for the Jockey Club has its moments, but is basically as overshadowed by proliferating plot twists as his romance with Irkab Athawa.

What's wanted in a violent denouement is that it seem boldly improbable but, by a whisker, believable, and because mysteries are ecosystems of right and wrong, fair. The culprit remained too enigmatic to inspire real dislike, and the climax, besides tying up too many loose ends for credibility, was a slightly abstract satisfaction.

"Frenzy," "sly childish impulse to hurt," "destruction and wrecking for its own sake" are names given the danger threatening Freddie. The havoc wreaked by this perverse driving force makes for a read that is (I'm resisting saying "as always") ingeniously entertaining, overall. The author's notes for Mr. Francis' books often observe that as a jockey he rode for the Queen Mother. At this point in his illustrious writing career, the Queen Mother might wish to note in her vita that the writer Dick Francis once rode for her.