Every image, every effect, is keyed to some kind of gross-out. What sets this film apart from the others somewhat is the artfulness with which it achieves a few of its effects. The film may be schlock, but it's a higher grade of schlock than we're accustomed to from this series -- which basically is all about being trapped in a dark room with monsters.

Not that Ridley Scott's Alien, James Cameron's Aliens or David Fincher's Alien 3 were bubblegum programmers. Despite their B-movie bunkum, they were outfitted with some of Hollywood's most inventively grody science-fantasy production designs. You felt mugged watching them, but at least they gave you something to pop your eyes at while the mugging took place.

Alien 3 -- the bummer in the series -- ended with the death of Sigourney Weaver's Ellen Ripley after she was impregnated with an alien queen. Finishing off Ripley was probably a commercial miscalculation, but, as it turns out, it sets up a shimmering premise for Ripley's return. In Alien Resurrection, scripted by Joss Whedon, we learn that Ripley has been cloned from preserved blood samples so she can birth the queen.

We see the "delivery," of course, in extreme close-up. A team of surgeons removes from Ripley's chest a baby alien queen. If you don't punch up the ick factor early in these movies, you lose your audience. Jeunet knows his audience.

Ripley, we soon discover, is aboard the colossal Auriga spaceship, staffed with science officers and enlisted personnel, all working for United Systems Military, which plans to raise tame aliens in captivity. Since the officers are played by the likes of weirdo specialists Dan Hedaya and Brad Dourif, it's clear the USM is up to no good. Dourif has perhaps his defining moment as an actor when, protected from the queen by an enclosure, he mashes his face against the plate-glass as if he were slobbering for a soul kiss.

A team of six mercenaries -- the captain (Michael Wincott), pilot (Kim Flowers), wheelchair-bound chief mechanic (Dominique Pinon), junior mechanic (Winona Ryder) and grunt (Ron Perlman), all capably performed -- links up with the USM and delivers its cargo of humans who will be hosts for the alien's eggs. The ensuing rumble lets loose Auriga's captive aliens. Ripley and the mercenaries -- in a deep-space variation on And Then There Were None -- spend the rest of the movie attempting to escape tentacles and pincers and goop.

Since alien DNA was involved in Ripley's cloning process, she's not altogether human. This gives Weaver an opportunity to play her usual tough-mama archetype with an alien overlay. Ripley isn't just a match for the monsters; she's part monster too. She's at war with herself -- Mother Courage with alien acid in her veins.

When Alien 3 came out five years ago, Weaver expressed her reluctance to once again play Ripley unless the role were truly challenging. When movie stars are in this yadda-yadda mode, it's usually a prelude to a fatter payday. And yet Weaver was right, of course. Cast in the same old way, her new tour of duty as Ripley might have come off as pure camp. As it turns out, she has more to work with in Alien Resurrection than she does in The Ice Storm, where she plays a bored adulteress -- another species of half-monster.

Weaver is able to take a schlock conception and turn it into a tour de force. Sky-high and straight-backed, she's imperiously graceful in this film; at times she resembles Martha Graham in the swooping, lyrical severity of her movements. Weaver plays Ripley as a feral, ravaged woman -- her face is at once frighteningly open and cloaked from all sympathy.

The primal psychological appeal of the Alien movies was always the notion of the beast within -- the monster id who suddenly pops out of your chest. Weaver brings out the metaphorical dread in this part-human-part-creature pulp. But Ripley represents what happens to you after the monster has popped out, and you're still alive. She isn't zombified by her condition; she's hyper-aware. The tension between her two natures has tuned her to a fine tautness. Her senses are alive to every quaver. In a couple of sequences, Ripley is like some preternatural Native American tracker, putting her ear to the ground to pick up impending vibrations from the alien swarm. She may want to flee, but she's also damn proud she's mother to the queen.

The film needs Weaver at its center. Like Terry Gilliam, Jeunet is such a frantically inventive futurist that, without powerful actors to ground his visions, his movies spin off into a gorgeous, exhausting nothingness. Gilliam's The Fisher King was centered by Jeff Bridges, Robin Williams, Mercedes Ruehl and Amanda Plummer. As extraordinary as Delicatessen and the even more lyrical The City of Lost Children looked, they wore you out in the same way that feature-length animated films, with their wiggy visuals and lack of human weight, can sometimes do. (Jeunet used to be an animator and still storyboards all his shots.) Alien Resurrection isn't as wildly inventive as his earlier films. And what a relief! If Jeunet had made a Hollywood creature-feature in his usual way, he might have wiped out most of the audience.

He has staged an underwater sequence that manages to be both terrifying and dreamily lyrical. Ripley and the mercenaries swim away from the pursuing aliens, and it's a true nightmare: The humans' movements are slowed by the water into a kind of sinuous ballet, while the aliens dart frictionless through the fluid. The entire passage has a frightful clarity. It's also a prime example of how an artist can take a conventional horror concept and really run with it. Jeunet is essentially a hired hand in Alien Resurrection -- he's preserving the franchise -- but in scenes such as these, he manages to join his own aesthetic obsessions with those of the popular audience.

Today's bottom-line Hollywood is no place to be an artist, but the realms of sci-fi and horror may still provide a playing ground where visionaries can try things out. Studio executives will license the experimentation because they understand that audiences want bigger and better gizmos. The irony is that -- if you're an artist in Hollywood right now -- you stand a much better chance of making a daring and "personal" film if you make a megazillion sci-fi epic such as Alien Resurrection than if you attempt a small-scale human drama.

Alien Resurrection.
Directed by Jean-Pierre Jeunet. With Sigourney Weaver, Ron Perlman, Winona Ryder and J.E. Freeman.

Rated R.
109 minutes.