By Ty Burr
Updated January 12, 1996 at 05:00 AM EST

The main characters in SHOWGIRLS (1995, MGM/ UA, NC-17/R, priced for rental) are not the exotic dancers played by Elizabeth Berkley and Gina Gershon. The main characters are their breasts. Screenwriter Joe Eszterhas and director Paul Verhoeven want you to think their movie is a daring screed that rips the lid off America’s hypocritical sexual repression to reveal the seething id below. Or something like that. But really, the movie’s a boob job.

Eszterhas and Verhoeven are both talented men who seem to delight in cynically selling out those talents in the name of what the public ”really wants.” With Showgirls, they’re trying to pass off a direct-to-video erotic thriller as a major feature film. But now that the movie’s available for rent, is there anything to distinguish it from the genuine article? Specifically, from the straight-to-tape LAP DANCING (1995, Triboro, unrated, priced for rental) and MIDNIGHT TEASE 2 (1995, New Horizons, unrated, priced for rental), both of which have been suspiciously timed to ride Showgirls’ coattails?

Well, yes: The breasts in Showgirls appear to be real. Lap Dancing and Midnight Tease 2 feature actresses so surgically enhanced that they resemble ’58 Chevy Impalas. There’s an inane purity in such insistence on precise geometric perfection; it’s as if every woman in the movie were wearing the same hat.

I know I’m sounding like a wildly objectifying pig boy here, but the movies aren’t exactly guilt-free either. Lap Dancing tries for balance with a female-empowerment story line, but the film keeps getting sidetracked by dully aerobic T&A routines. Lorissa McComass plays Angie, a wallflower L.A. wannabe actress who taps into her wild side by peeling at a local club; her statuesque roommate, Claudia (Tane McClure), overcomes her fear of singing in public by belting out a triumphant number at the movie’s climax — in the nude. The message — that stripping can help one overcome inhibitions — has a certain validity, but Lap Dancing views its heroines from the vantage point of the voyeurs in the audience. The plot’s as big a con as lap dancing itself, and the shoddy script, clumsy editing, and wan acting (with the exception of the caustic McClure) give the charade away.

Midnight Tease 2 is worse, since it’s a thriller that plays the sex-equals-death angle for maximum sleaze. In the interests of critical disclosure, I’ll confess to never having seen the original Midnight Tease, but like the actresses’ breasts, these movies can probably stand on their own. Someone is smothering the strippers at a club, and one victim’s sister (Kimberly Kelley) goes undercover to smoke the killer out; as in Lap Dancing, the movie grinds to a halt for laughably hyperactive nudie routines. Tease 2 tries to portray its strippers as genial working stiffs, but the movie seems to take a greater pleasure in killing them off.

At least Showgirls gives you an unintentional laff riot for your money. The biggest howler is the movie’s assumption that the glitzy Vegas lifestyle depicted here represents the pinnacle of sophistication. When Nomi (Berkley) clambers from strip clubs to the Stardust’s stage extravaganza, Goddess, it’s depicted as a step to freedom, but the show itself is just an overly garish Oscar-night number. And how does the audience know that the Stardust manager (Kyle MacLachlan) is one classy guy? Why, he’s the one with neon palm trees around his pool.

Kitsch value aside, Showgirls pulls the same maneuvers as the other two movies. As the cast members act out the wee plot from the neck up, the camera settles with meditative constancy on their bosoms. Which quickly becomes boring, since Eszterhas and Verhoeven forget that the essence of eroticism lies in what isn’t shown.

By this rule, the R-rated home-video cut of Showgirls should be more of a turn-on, since that version drops 61 seconds of footage from a nasty rape, a long lap dance, and a histrionic swimming pool sex scene that represents Showgirls’ bid for the Camp Hall of Fame. The tamer cut was made for sale at chains like Blockbuster, which doesn’t carry NC-17 titles but does carry unrated tapes like Lap Dancing and Midnight Tease 2. This way, Blockbuster gets to hew to its policy, the renter gets the promised breast-fest, and everyone goes home happy. Except viewers expecting a good time. For them, each of these movies is simply a bust. Showgirls and Lap Dancing: D Midnight Tease 2: F