We have tolerated purple vegetables, BMW salesmen and baby-on-board signs, but we must draw the line at yuppie gangster movies. Or else they'll make more of them. It's one thing to accept corrupt lawyers and shyster stockbrokers, but Porsche-pinchers? Yes, the men in the Rolex watches take to stealing exotic autos in "No Man's Land," a low-horsepower chase movie with Charlie Sheen and D.B. Sweeney.

Sheen, the foxhole inge'nue of "Platoon," sneers a lot as Ted Varrick, a contemptuous chop shop chief and suspected cop-killer. As the product of an upper-class background, he steals for thrills and to get back at his parents, the jet-setters. "Lifestyles of the rich and aimless," he dubs his circle, which turns out to be a pretty good description of the movie.

Sweeney, who debuted as the recruit in "Gardens of Stone," plays his new partner, actually an undercover cop named Benjy Taylor. A rookie from a kindly blue-collar family, he is dizzied by the high-speed chases and all the champagne he can drink.

Mostly, the movie is set in underground parking lots where the car thieves sneak up on their quarry by carrying Rodeo Drive shopping bags as disguises. They hot-wire Porsches, squeal round the labyrinthine ramps, make big bucks fast and dance the night away at clubs frequented by women with successful breast implants. Benjy, who is positively as cuddly as his doggy namesake, realizes this is nothing to sniff at and becomes unsure of his true loyalties.

Then Varrick's kid sister -- Isabella Rossellini clone Lara Harris -- stares her way into his heart. They enjoy a chaste love scene and some wooden dialogue and we just don't know what the hero will do now that he has seen her midriff.

Like a teen-age Popeye Doyle, he's in a no man's land: Cop or car thief? Porsche or sensible squad car? Writer-producer Dick Wolf conceived the conundrum, which is as tired as the "Miami Vice" and "Hill Street Blues" shows with which he's been closely involved. Peter Werner, with plenty of documentaries and "Moonlighting" episodes to his credit, directs this out-of-gas look at the young and the mobile. What this movie needs is more macho, more moxie, more attitude. Fill it up, and make it high testosterone.

No Man's Land, at area theaters, is rated R for violence and profanity.