Demi Moore teams up with director Ridley Scott to prove that a "chick flick" can be as bloody, brutal, and testosterone-pumped as anything the boys can dish out in this blockbuster summer. Both Moore and Scott could use a hit, and G.I. Jane is, accordingly, a big, loud, and ferocious gender-bender that plays to the balcony seats.

G.I. Jane's critics have pointed out that there's nothing new in Scott's viewfinder this time around, and it's true that the film recycles every movie cliche of military training. But Scott is a filmmaker who thrives on putting a fresh spin on the familiar. The 1978 Alien was a science fiction slasher movie that played fast and loose with conventions of both genre and gender. With a big assist from Douglas Trumbull's special effects and a smartly bleak script by David Webb Peoples, Scott's Blade Runner became probably the most influential genre movie since Star Wars. And Thelma & Louise, of course, turned the tired buddies-on-the-run story into a genuine pop culture tremor. Small wonder that, after trying his luck with the far less bankable 1491: Conquest of Paradise and White Squall, Scott finds himself once again looking for the fault lines.

So what's G.I. Jane? Here's the high-concept rundown: "Demi Moore in training to become the first female Navy SEAL." She's sponsored by a grandstanding senator from Texas (Anne Bancroft), who turns out to be a snake with allegiance only to political obligations. She's trained by grandstanding "Master Chief" John Urgayle (Viggo Mortensen), whose bruising, R. Lee Ermeyesque verbal style is balanced by quotations from D.H. Lawrence, of all people. And she's sharing quarters with a bunch of skeptical recruits who find her tampons, among other things, too much to bear. And, oh yeah, her head is shaved. That's her first androgynous step toward gaining acceptance among the guys.

The training regimen for these wannabes is so cruel that fully 60 percent of them are expected to drop out before the course is complete. Those that don't will be mentally abused, kicked in the teeth, locked in cages, and forced to make a meal out of leftover "chow" found in garbage cans. (They'll also be forced to write a 500-word essay on "Why I Love the United States Navy" to the midnight accompaniment of Puccini, of whom Urgayle seems perversely fond.)

Sound familiar? Well, this time around it's actually quite entertaining, infused with a singleminded confidence and hoisted along by Scott's visual flair. The confidence comes courtesy both the director and his star. Jordan O'Neil is quite possibly the perfect role for Moore, and maybe the only one she can play with any credibility at this point in her strange career. Her famously sculpted body, seemingly all curves and sweat under blue light, is certainly photographed to better effect in support of this dire physical tale than it was in the ridiculously preening Striptease. And Scott stages every scene like this is the most important story he could possibly be telling. That enthusiasm is infectious, and I admit to being easily swept up in the movie's rousing, if manipulative, spirit.

With striking camerawork by Hugh Johnson (including a funky zoom-like trick for combat sequences) and energetic editing by Pietro Scalia (JFK), Scott comes across once again as a filmmaker who knows exactly what he's doing. G.I. Jane is so stylized as to seem otherworldly, which is key to enveloping viewers in its unpleasant milieu without alienating them. Physical training has never seemed so bizarre -- Ridley's recruits do push-ups in the surf at the orders of an apparent madman while a helicopter hovers nearby, like some winged demon. The chopper blades make an interior whoosh-woosh-woosh noise like the ones in Martin Sheen's head at the beginning of Apocalypse Now. Before long, Moore will find herself crawling beneath barbed wire while her trainers and tormentors fire bullets and rockets overhead. And ultimately, some particularly nasty war games will have her spittin' teeth and dealing with a master chief who's teaching her a lesson by pretending to rape her.

Well. The movie is pretty brutal, and it's not recommended for those with a serious aversion to violence. It might even be a problem for those who don't understand why in the world a woman would want to put herself through this kind of abuse, but it's best read for metaphor rather than realism. (I thank Scott for refusing to resort to blind jingoism, even when the company winds up, conveniently, in Libya.) G.I. Jane is, really, the ultimate test case for the end of gender-based segregation. I'd be very surprised to learn that SEAL training is every bit as recklessly violent as what's depicted here, but verisimilitude is not the point. Vicarious satisfaction is. And maybe catharsis.

The screenplay by David Twohy (Waterworld and The Arrival) and Danielle Alexandra (from Alexandra's story) is as smart as it is facile, blending political melodrama with grunting histrionics. The picture could have been tightened -- and, perhaps, improved -- by jettisoning the final half-hour and devising a different way for O'Neil to prove herself in the eyes of the U.S. military. And while the political posturing and backpedaling of Senator DeHaven is fairly entertaining -- due mostly to Bancroft's bravura performance -- it's ultimately a distraction. Most extraordinary is Mortensen (seen most recently in Daylight and The Portrait of a Lady), playing a frighteningly whacked-out Master Chief. Moore herself is, at least, up to the task before her. Her jaw is set and her body is buff and she doesn't overplay the role. That's about all it takes. She looks determined enough to make you believe she's the woman who could do this. That's an accomplishment in itself.

As role models go, you could do a lot worse.