A FORCE OF ONE -- At more than 20 area theaters.

"A Force of One," has a simplistic plot, lowbudget sets and sloppy editing.

It's pretty good.

Not only does it move along at a faster clip than many a higher-budget film, but it's done without a lot of gore -- no small feat in a martial-arts movie. This is not to say there's no violence: There is. But it's tempered by a constant, underlying theme of discipline and restraint, so the emphasis is on the"art" rather than the "martial."

Another plus is that the romantic leads, Jennifer O'Neill and Chuck Norris, actually seem to like one another; they're relaxed and at ease before the camera, and their scenes togethr area pleasure to watch. The fact that Norris is a former world karate champion who's had more experience breaking boards than acting makes this all the more impressive.

Also, there's only one car-chase scene.

O'Neill plays an undercover police officer on the trail of a cop-killer in a small California town. "Hey! Maybe it's one of those karate weirdos like in the movies," she tells her boss in a police department meeting.

"Sounds pretty feeble to me," he says, a comment that could equally be applied to the plot. But he lets her talk Chuck Norris, who owns the neighborhood karate studio, into helping track down the bad guys.

O'Neill is all business in a close-cropped haircut (she's going gray, and looks terrific) and adds a touch of class to her role as the tough-yet-vulnerable cop who falls for Norris.

And there are some charming scenes, as when Norris teaches karate to a circle of bowing, pajama-clad kiddies, including one pig-tailed little girl who maages to flip him. There are even some witty moments, when he tries to teach karate to skeptical male cops. Norris seems to genuinely enjoy his work, and when he goes on about discipline and respect it's obvious that he knows what he's talking about.

Unfortunately, at the end of the movie Norris really rips into someone, and there's the sickening sound of snapping vertebrae so popular in martial-arts movies. Oh, well. Maybe the restraint was just too good to last.