Grade: B

The first-ever teaming of Hong Kong icons Jackie Chan and Jet Li is the main selling point of “The Forbidden Kingdom,” and Rob Minkoff’s movie gives both of them ample opportunity to show off their dexterity and sense of humor, what with their multiple roles and frequent over-the-top fight scenes. But while they’re fun to watch, their die-hard fans may be a bit disappointed, because the picture is actually an old-fashioned boys’ adventure yarn in which they play second fiddle to a typical kid who—like those in so many in recent pictures—is the chosen savior of the (or at least a) world. Just think of “The Seeker,” only—thankfully—a good deal better.

The youth in question is Jason (Michael Angarano), introduced as a fatherless Boston teen put upon by the school toughs led by Lupo (Morgan Benoit), the obligatory sneering bully. His only pleasures in life, it seems, are the rare kung-fu DVDs he finds in the Chinatown pawnshop of doddering Old Hop (Chan, in heavy makeup), where he finds an ancient golden staff Hop says he’s been holding for a special person. Unfortunately, Lupo and his gang force Jason to get them into the shop so they can rob it, and in the melee that follows, Hop is shot and Jason, forced to jump off a rooftop while holding onto the staff, is magically transported to ancient China, a realm ruled by the cruel Jade Warlord (Collin Chou).

Jason is saved from the warlord’s soldiers by Lu Yan (Chan again), a “drunken master” who identifies him as the traveler destined to return the golden staff to its rightful owner, the Monkey King (Li), an immortal who was trapped as a stone statue centuries before by the evil warlord. By freeing him, Jason will return the realm to peace and happiness with its rightful emperor.

Jason and Lu Yan set out for the warlord’s distant castle, now accompanied by Golden Sparrow (Liu Yifei), a young woman seeking vengeance on the warlord for killing her family. Soon they’re joined by The Monk (Li once more), who initially steals the staff but, after a battle with Lu Yan, is revealed as an ally.

The quartet continue their journey through desert and forest, attempting to survive attacks by the warlord’s bounty-huntress (as well as sorceress and master bow-woman) Ni Chang (Li Bing Bing) while the two men train the hapless boy in the martial arts. Eventually Jason proves his mettle in a final confrontation at the Jade Warlord’s palace, where all the parties congregate. And in a postscript the boy must return to his own world and face Lupo and his crew—happily with some of the skills he learned “long ago, in a kingdom far away” and a couple of lingering friendships as well.

In essence “The Forbidden Kingdom” is just a far flashier version of the “Karate Kid” scenario, chock full of colorful costumes, photogenic locations, spectacular sets, flamboyant combat choreography and splashy CGI effects. And, of course, two Mr. Miyagis in period dress, played by the masters of the genre. The result is fun in a silly schoolboy way that should appeal to adolescent boys in particular. Its appeal to older audiences, even fans of Chan and Li, is less certain, however; they may be peeved that the idols are reduced to essentially common foils for a teenaged hero.

But while one can imagine Chan and Li having been cast in something more respectful of their iconic status, the fact is that John Fusco’s script is cobbled together from the conventions of kung-fu fantasies, and the result is certainly no worse than the junk the two have been cast in for their previous Hollywood outings. And the old pros certainly do all that’s asked of them, each playing to his strengths, with Chan doing his broad comedy and Li showing his range as both the stoic monk and the frantic Monkey king (a figure that kids are more likely to find enjoyable than their elders will). Angarano, who’s developing a very long resume in record time, makes an appealingly vulnerable young hero, and Yifei is dexterous as well as pretty as the young woman who becomes his romantic interest. On the villainous side, Chou and Bing are coolly malevolent foes, and they’ve got good moves, too.

The picture looks sumptuous, with Peter Pau’s lush widescreen cinematography setting off Bill Brzeski’s colorful production design, Eric Lam’s art direction, the sets by Fu De Lin, Lu Zhi Kui, Huang Wei Min, Wen Yu Ci and Lan Bin, and Shirley Chan’s costumes. And Minkoff’s direction keeps things moving along nicely, although the bookending contemporary sequences play poorly and he can’t do much with the more juvenile jokes.

With Chan and Li finally brought together, one might have hoped for a genre classic. “The Forbidden Kingdom” isn’t that, but it’s a reasonably entertaining throwback for the younger set, which nostalgic adults can also enjoy if they don’t go expecting too much.