March 29, 2002 | Some movies are immoderately enjoyable simply because they don't live down to your worst expectations. Yes, I know, we critics are supposed to walk into movies without any negative preconceptions, and impartially judge each work on its own merits, and blah, blah, blah. I have to admit, however, that I approached Clockstoppers, a high-concept, teen-skewing sci-fi comedy-adventure, fully prepared for something that stunk out loud. But I wound up being amused - and, yes, grateful.

If, like me, you've been turned off by the willy-nilly silliness of the coming-attraction trailer, which promises something as aggressively witless as a sub-par, live-action Saturday morning kid-TV show, take heart. The screenplay credited to Rob Hedden, J. David Stem and David N. Weiss isn't exactly sophisticated, but it's not unduly childish, either. And director Jonathan Frakes, who knows a thing or two about briskly paced and smarter-than-average sci-fi entertainment, keeps everything light, lively and, more often than not, pleasantly exciting.

Just in case you tuned in late: Frakes co-starred for several seasons on Star Trek: The Next Generation, and directed the last two Star Trek feature films. By this point, he likely is more than ready to move beyond warp speed, and ratchet up to "hypertime." A good thing, too, because hypertime, according to Clockstoppers, is a fantastical process whereby a human being's speed is so drastically accelerated that he or she is invisible to everyone else, and everyone else appears to be frozen stiff to the hyper-speeding human. In short, it's the speed at which my long-suffering editors dearly wish I would write my reviews.

If memory serves me correctly, this same gimmick was used in an old episode of The Wild, Wild West. But never mind: It's a reasonably clever premise, and Clockstoppers has a fair amount of fun with it.

Jesse Bradford makes an appealing impression as Zak Gibbs, an enterprising teen who's trying to raise money to buy a vintage Ford Mustang by purchasing thrift-shop items that he repairs for resale on eBay. Trouble is, his science-professor father (Robin Thomas) is too caught up with his teaching and research work to spend much time with Zak, or to even notice what a bitchin' set of wheels his son wants to purchase.

When Dad goes off to yet another out-of-town science convention, he leaves behind a cool-looking wristwatch that he received from a former student. Zak accidentally gains possession of the timepiece, and slips it onto his wrist. Then the really important stuff starts to happen, as Zak quickly discovers that, as long he's wearing the watch, he and anyone in close contact with him can enter - tah, dah! - hypertime.

What's that you say? Yes, you in the red cape and the blue bodysuit! You want to know if he's faster than a speeding bullet? Hah! He's so doggone speedy, he can literally walk on water. So there.

At first, Zak is content to while away hypertime by attending to relatively innocuous pastimes - like impressing Francesca (Paula Garces), a beautiful new classmate, by rapidly raking leaves in her yard. Or helping Meeker (Garikayi Mutambirwa), his best friend, who needs all the help he can get to win a DJ competition.

(Meeker, it should be noted, represents a rather demeaning teen-movie stereotype - the jivey African-American buddy of the white lead character - and his appearance in this otherwise pleasant film is, at best, a minor annoyance.)

Complications arise, however, when Dopler (French Stewart), the former student, pops up to retrieve his watch. Then the bad guys, led by an evil technology tycoon (Michael Biehn) who financed Dopler's time-tripping in the first place, kidnap Zak's father to further their wicked schemes. A happy ending is delayed for a reasonable amount of time, but not so long that Clockstoppers wears out its welcome.

The supporting players are mostly first-rate - even Stewart, normally not the most subtle of farceurs, is uncommonly restrained - and the special effects are really nifty. Not being a physicist, I can't speak with any authority about the weird science that propels the plot. It does seem to me, though, that anyone moving at hypertime speed might run the risk of self-immolation. And I'm almost certain that if someone moving at hypertime speed tried to physically adjust or even slightly move someone moving at normal speed - well, it wouldn't be pretty. But, to paraphrase Michael York's memorable advice to the audience in Austin Powers: The Spy Who Shagged Me, the people who made Clockstoppers didn't worry about that, so it's probably a good thing if you don't worry about it, either.