Giving his first English-language performance to show any range of acting ability, martial-arts superstar Jet Li is inspired in "Unleashed" as a man-child raised in a cage by a minor-league Glasgow loan shark and trained for one Pavlovian purpose: To instinctively attack like a dog when his master (Bob Hoskins) snaps off the collar kept around his neck.

The threat of "you don't pay, the collar comes off" is often all the vicious Hoskins needs to scare every penny due out of tardy debtors -- but not so often that Li doesn't get a good workout throughout the film. Director Louis Leterrier ("The Transporter"), master fight choreographer Yuen Wo-Ping ("Kung Fu Hustle," "The Matrix," "Kill Bill") and the ever-limber Li unleash several raucously raw and instinctive fight scenes when Hoskins lets his animal loose.

But "Unleashed" is ultimately a character-driven story, and Li rises to the occasion when a twist of fate, machine-gun fire and car-wreck carnage set him free with no skills for coping in the real world. Scared and confused, he's taken in by a blind piano tuner (Morgan Freeman) and his sweetly gawky 18-year-old stepdaughter (Kerry Condon), who are similarly out of their element as Americans living in Scotland (where, curiously, no one speaks with a Scottish accent). Through this surrogate family, his humanity begins to emerge in a series of well-written scenes in which Li perfectly balances his character's wide-eyed innocence and newfound joy with the violent impulses that lurk uncomfortably in the dark recesses of his battered psyche.

Written by Luc Besson ("The Professional," "The Fifth Element"), who has a gift for creative action-movie concepts but a bad habit of dumbing them down, "Unleashed" has its clumsy moments, especially when it comes to the folksy wisdom and altruism thrust upon Freeman (who nonetheless makes his role believable). But the movie is balanced out with more interesting characters in the girl (who in this kind of movie would normally be a babe), the gangster (Hoskins turns him into an extremely twisted father figure), and Li's hero, whose new life (and new respect for life) is threatened when Hoskins returns from near-death to hunt him down.

Leterrier makes savvy use of music as a simple metaphor for Li's self-discovery, builds superb tension into scenes in which Li struggles against his killer instincts, and knows enough to let the powerfully intuitive fights created by Yuen speak for themselves in long takes that display Li's skills instead of flash-editing the life out of them, as has become all too common in Americanized kung fu movies.

Had Besson and Leterrier been confident enough in the genuinely potent drama to reel in a few preposterous elements, "Unleashed" (which goes by the much better title of "Danny the Dog" overseas) might have been one of the best martial arts movies yet made in English. But while it isn't perfect, the few unfortunate nods to convention are certainly forgivable when the rest of the picture stands uncommonly above the genre norm.