Let it be said, by way of a small gesture in the direction of caveat emptor, that John D. MacDonald certainly takes his jolly good time about getting this, the "20th adventure of Travis McGee," off and rolling. The opening chapter lurches this way and that as McGee--his own narrator, as usual--backs and fills in an effort to connect the events that are to follow in "Cinnamon Skin" with those most recently completed in "Free Fall in Crimson." MacDonald comes out of the blocks like a turtle in a 100-yard dash.

But--did you expect otherwise?--once out of them, MacDonald is off on a high-speed chase of precisely the sort that his hundreds of thousands of loyal readers have come to expect of the McGee novels: "Like a child's game in the Sunday comics. Connect the dots and find the animal." Ah yes, the animal. Almost always there is the animal, an especially loathsome specimen of the human variety, a man with a demented appetite for murder or sex or drugs or money--anything that sets him on a path of destruction and McGee on a path calculated to cut him off at the pass, preferably at the last conceivable opportunity.

Here, connecting the dots involves the joint labors of McGee and his friend Meyer, the brilliant and eccentric economist who, like McGee, ties up his houseboat at a Fort Lauderdale marina. The trouble is that Meyer's boat has just been blown to kingdom come, with a local fishing guide and Meyer's niece and her new husband aboard. Except that McGee and Meyer soon come upon a photo that suggests the husband, Evan Lawrence, was not aboard. The odor of rat is in the air.

A rat, our doughty investigators soon enough realize, of a particularly odious stripe. Evan Lawrence is only one of many names he has taken in a long history of pursuing, seducing and murdering an unknown number of women. McGee describes him: "My guess would be that he is a hunter. Women are the game he specializes in. He is a loner. A rare kind of loner, a man who seems affable, agreeable, gregarious, fun to have around. That is his act. That's the way he comes up on the blind side, upwind, every move calculated." The effort to track him down takes McGee and Meyer, together and separately, to various places in Texas, to upstate New York, back to Florida, finally to the climactic encounter in Cancun.

The chase is as gripping and diverting as usual; one of MacDonald's most admirable qualities as a novelist is that he almost unfailingly manages to deliver precisely the pleasures that his readers anticipate--a quality too-little noticed and remarked upon among writers whose principal business it is to entertain. But also as usual, MacDonald provides a good deal more than mere diversion. He is a tinkerer in the grand old American tradition, a man who loves to learn how things work and a writer who loves to pass that knowledge along to his readers; here he has much to say, all of it interesting, about how fishing boats work and how geologists explore for oil. He also takes pleasure in tracking the continuing emotional adventures of Travis McGee, the loner who would love to be a husband and father except that he couldn't stand it.

"It made me wish my life had been different and I'd had some sons. Sure, McGee. What you want are the full-grown variety, big and sturdy and loyal and true. But you never wanted what came in between: diapers and shots, PTA and homework, yard mowing, retirement programs, Christmas lists, mortgage interest, car payments, dental bills and college tuition. You made your choices, fellow, and you live with the results. And if in the end there is nobody to give a single particular damn when you die, that too is part of the bargain you made with life."

This is the point: Without thumping any turgid thematic chords, MacDonald reminds us that the free life is not all it's cracked up to be. We read McGee--in particular, I think, we men--because his life of adventure, romance and independence is a contemporary, sun-tanned variation upon a yearning that is deeply embedded in American mythology; in the company of McGee, we vicariously light out for the territory and escape from Aunt Sally's civilizing ways. But MacDonald, like Twain, understands that it is the fate of most of us to be tied in one way or another to someone else's apron strings, and that McGee, for all his derring-do, exists in a boy's dream rather than real life. That MacDonald makes each new chapter of that dream believable and occasionally breathtaking is testimony to his undiminished skills; after 66 books, he is still going strong.