The plot is pure choose-your-own-adventure: A bullied fanboy from South Boston (Michael Angarano) is teleported back into a fantasia of feudal China, where he's singled out as the long-anticipated "Chosen One" prophesied to topple the despotic warlord. Our nominal hero then recedes behind the pair of Mr. Miyagis who adopt him: Jackie Chan (in a Lisa Bonet wig) and warrior-monk Jet Li (English line readings: 75 percent intelligible). This is the first collaboration between kung fu's Astaire and Kelly, and on those terms, it disappoints. Like so much in Rob Minkoff's movie, the fight arrangements by choreographer Yuen Woo-ping aren't so much bad as undistinguished: The camera placement is off, the tempo unvaried, and Chan's movements are obscured by his piled-on robes. The cinematography lacks storybook indelibility; Collin Chou's Jade Emperor is a stock archvillain (though Li Bingbing's bullwhip-toting "White Haired Demoness" is lovely). And then there's the scene in which Li actually pisses in Chan's face — a degradation familiar to viewers incensed by the demographic-outreach casting of white-dude Angarano. Taken as a whole, though, it's an amiable lost-and-found of epic-adventure tropes. Just as I still illogically treasure Willow, many a 10-year-old who sees Forbidden Kingdom will remember it fondly in spite of its flaws.