Several months ago, while watching TV at a friend's house, I saw a promotional trailer for The One appear on the screen. "What's this?" someone asked. "The new Highlander movie," I replied. It's not, of course, but tell me that didn't occur to you when trailers for The One started showing.

It's a well-used sci-fi trope: alternate universes, alternate selves, and someone jumping from one to the next, wreaking havoc and seeking to climb to the top of the bad-ass heap. In this case, that someone is Jet Li, who as Yulaw goes rampaging from one universe to the next, killing off alternate selves to amass their strength, speed, and skill to himself. He's done 123 so far; one more, Jet Li as Gabe Law, and he'll either become God or destroy reality, no one's quite sure and no one seems to care. Not a very original premise, but one that it shouldn't be too difficult to pull off in an entertaining manner, particularly when you've got Li on board.

And The One is reasonably entertaining, if by "reasonably entertaining" you're prepared to settle for a music video (back when MTV had music videos) or a shoot-'em-up arcade game. It's also a source of inestimable frustration, because this film fails to live up to its potential on every count. It can't decide whether it's a martial arts flick, a hard science fiction film, or a philosophical poser. And instead of going for one of these things with elements of the other two, as The Matrix did so successfully, it tries to be all three without dedicating itself to any of them. Great: a flashy sci-fu feature with commitment issues. Sounds like a bad date.

James Wong and Glen Morgan, who brought us "The X-Files" and the short-lived but promising "Space: Above and Beyond", seem to be out of their depth here. They've done science fiction before, but when the opportunity arises to do some really interesting parallel-universe mind-bending, they settle for pedestrian contrasts (in one universe, we're greeted by the LAPD; in another, by the L.A. County Sheriff's department) and pale jokes (a parallel universe where Gore is president; that's this film's idea of cleverness). A related problem is that logical fallacies abound, and the viewer has to do far too much work to make sense of it all. Let me put it this way: when Roger Ebert can point out the logical flaws in your movie, that's a sign you really haven't thought your premise through.

And that would be fine, if all The One really wanted to do was show everybody a good time. But then why bother with the flashy sci-fi setup? And the fight scenes, necessary set pieces in a movie like this, have no more depth or originality than the filmmakers' exploration of their own premise. Everything in them has been done before, and generally better, often by Li himself, whose considerable abilities here vanish in a haze of special effects, beat-heavy music, and slo-mo wire work which, again, was done better in The Matrix and is here overused to the point of ridicule. The fact that one of his opposing characters needs to strip down to a t-shirt for the two characters' final showdown, so that we, the viewers, can tell them apart, is a peculiar highlight of this film's superficiality. Until the good Law finally clues in and uses what looks like tai chi on fast forward to defeat his opponent, there's no other way we can tell them apart. Li is a better actor than that, as anyone who's seen him in The Tai Chi Master or the epic Once Upon a Time in China series can attest. Here, he's either wide-eyed and stone-faced, or grinning like a loon. One would hope that killing off your doubles in alternate universes would also grant you a complete personality, but that doesn't seem to be the case. Pity.

In fact, none of the actors get to do much, including James Morrison and Tucker Smallwood, two staples of Wong and Morgan projects. Delroy Lindo is shamefully underused, and Jason Statham talks out of one side of his mouth all the time as if he has a James Dean complex. Carla Gugino gamely does her best, but the mileage she gets out of her part only underscores how little the cast is given to do. The whole movie feels rushed, as though Morgan and Wong know how much they're trying to cram into this picture, but they're so busy hurrying on to the next thing, that they forget to spend time on what's actually happening. It makes for something of a commentary on modern life, but it also makes a pretty unbelievable movie. That may seem like a strange word to apply to a movie like this, but it's a feature of good storytelling that the strangest, most unlikely, unreal events can be made plausible. The One doesn't manage to sustain this much past the opening act, with the result that, at the end, you have a clutter of unrelated ideas instead of a unified whole.