Jo's about-to-be ex-husband, Bill (Bill Paxton: U-571, A Simple Plan), left stormchasing when he and Jo split, but now he shows up in the field with his fiancée, Melissa (Jami Gertz), with the express purpose of getting Jo to finally sign their divorce papers. Though he keeps insisting to his-- er, Jo's crew that "I'm not back!" it's obvious that he misses the thrill of the chase, and it doesn't take much to get him to tag along for the day.

Twister is thin on plot, but what there is of it is enough to keep the movie moving through spectacular sequences of tornadoes doing their thing, wreaking havoc and inflicting incredible damage to anything in their paths. Action movies tend to merely one-up their predecessors, with bigger explosions or more elaborate car chases, but the effect of that is that they all start to blend together in a generic mishmash of movie memories. But Twister is unforgettable because it puts on film imagery we've never seen before, thanks to what was, at the time, only four years ago, revolutionary new digitally produced special effects. Computer technology allowed de Bont to tell a story visually that could never have been told previously so convincingly, from skies that are ominously "goin' green" to the twisters themselves. And so we also get the likely more traditionally created images of Jo's dad, in a flashback, getting carried away by wicked winds, a drive-in theater screen sliced up by a tornado, and raining tractors and rolling houses, massive objects tossed about like toys.

As befitting a story that wouldn't be possible without advanced technology, Twister casts scientists in a positive light, when all too often they're portrayed, at best, as amoral tinkerers in things they should be leaving alone, or, at worst, as outright villains. The geeks are cool here, heroes out to save lives and make the world a better place through science and technology. (And geeks they are: Listen for them quoting, as geeks are wont to do, from classic cult films like Repo Man and Star Wars.) And they're led by another rarity in the movies: a woman who is driven to the point of obsession by her work who doesn't end up punished for it, and doesn't learn any clichéd lessons about how she'd be so much happier if she just started pumping out children, either.

The bad guy here is a scientist, too -- Dr. Jonas Miller (Cary Elwes: Cradle Will Rock, Liar Liar) -- but what makes him the bad guy is not that he's using science for evil ends but that he's a "corporate kiss-butt," with fancy equipment and a fleet of sleek black minivans, all paid for by corporate sponsors. "He's in it for the money" is the worst thing Bill has to say about him, a big insult coming from a group using old, sometimes broken-down equipment and driving around in dilapidated station wagons, campers, pickups, and schoolbuses. (Bill, it must be noted, was on the verge of going in the same direction as Miller, with his new job as a TV weatherman -- a fate his re-encounter with Jo and her crew saves him from.)

Okay, the script -- by Michael Crichton (Jurassic Park, The 13th Warrior) and Anne-Marie Martin -- is absurd in parts, and it has an annoying habit of relying on the obvious for its attempts at humor. ("No way" can Jo use Bill's beautiful new truck when hers is trashed; cut to Jo driving his truck. "We are not invading my aunt" for lunch, Jo insists; cut to the gang invading her aunt.) But that's more than made up for by the real chemistry between Hunt and Paxton, and the appearance of two actors -- Philip Seymour Hoffman (Magnolia, The Talented Mr. Ripley) and Jeremy Davies (Up at the Villa, Saving Private Ryan) -- who prove, with small roles they imbue with real character, why they deserve to be as celebrated as they are now becoming.

But mostly, it's the twisters that make Twister so impressive. If you've got a DVD player and a good sound system to project the rumbling growls of the storms, you'll feel like you're right in the middle of the action. Cool.