BOOK REVIEW / NOVEL : Caught Between Illusion and Reality : PAINTED DESERT <i> by Frederick Barthelme</i> ; Viking $22.95, 245 pages

Frederick Barthelme’s first books portrayed the disconnections of his 1980s yuppies in deceptively neutral terms while splicing a single subliminal frame of death threat into their VCR videotapes. More recently, expanding the threat, he has gone from silky underground provocateur to silky guerrilla warrior, and his target has evolved with the times.

Like Tom Wolfe, Barthelme’s eye and ear capture unerringly the moment he lives in. Like Wolfe, but more so, his heart divides itself between a trampled yesterday and a dubious tomorrow: twin vectors of contention with a today so bland and unfiltered that we could be eavesdropping on it through the walls of the upscale motels his characters stay at.

His present target, which suits him beautifully, is the revolution portended by the Internet and other forms of virtual reality. He is of the counterrevolution; one that has sprouted so quickly in the last year or so that it may risk getting out in front of what it is chasing. Coinciding with several recent nonfiction books that question whether the cyberworld can sustain human life, he has published a witty and agile anti-Internet novel--one of the first or perhaps the first.

“Painted Desert” is a peripatetic philosophical discourse, an argument pursued while walking around. In this case, walking takes the form of a ramble through the Southwest in a luxuriously incorrect, gas-guzzling, leather-seated road-wallower. “The big Lincoln flowed down the highway. I set the cruise control on 75 and sat up high and steered as if we were in a gigantic inflatable,” the narrator tells us.

He is Del, mid-40ish, laid-back professor at a junior college on the Mississippi gulf coast, and a character in a previous Barthelme novel. He is accompanying his mid-20s girlfriend, Jen, an Internet-adept who downloads her e-mail at each stop, and is as ostensibly activist as Del is ostensibly placid. An inveterate “cybermuckraker,” Jen vacuums up world and national awfulnesses from her electronic billboards, reassembles them into potted screeds, prints these out and posts them on the campus trees, or feeds them back into the electronic network.

“We need to do something. We can’t sit here and watch it on television any more. I can’t take that,” she says. “There’s something about being there physically. Like occupying the physical space.” Her notion is hazy and variable--at one point she imagines visiting Reginald Denny’s assailant in jail and confronting him--but its passion has an old humanity to it. It is Don Quixote’s need to go out and fight the knightly battles that books have stuffed into his head.

Like Cervantes, Barthelme portrays the passion for satirical purpose: The illusion of reality can destroy reality. Only in this case it is the Internet blizzard of effortless data, instead of the effortless fantasies of medieval romance. Jen’s project is absurd but cannily revealing. It is also, as Barthelme follows their journey, filled with a variety of beguilements.

Almost before they start out, they have picked up Jen’s father, Mike, a wealthy retired insurance man and, embarrassingly, only six years older than Del. Mike’s orderly life is ripe for transformation; he joins the quest, contributing his car, expenses and, as a Kennedy assassination buff, a need to visit Dealey Plaza in Dallas. A day or so later, they acquire Pam, Jen’s former roommate. Her particular objective is a desert shrine where a number of old Cadillacs are jammed vertically into the ground.

Tossed in a four-way swirl of speculation, argument, anecdote, and free association (recall Sancho Panza’s immense woolgathering discussions with Don Quixote), their purposes meander. The concrete highway supersedes the information superhighway. Other things take over: the landscape, the stops, the inveiglement of maps and alternate routes.

As with any long trip, “Painted Desert” has moments when it seems that nothing but time is passing by. It is talky, but the talk is entirely alive; these are not speeches but people discovering in mid-sentence what they want to say or, sometimes, not say. Barthelme’s message--information for which no human pain is expended either to acquire it or to use it can stifle the spirit--is stitched lightly and deftly. He has endowed his four endearing characters and their journey with what seems to be the fun of a lifetime, and only the seriousness that it is able to take.