In an attempt to garner a breakout American audience, Jackie Chan's latest kung-fu action-comedy, "Rush Hour," has him cast as a mis-matched police partner with the speed-talking, one trick pony comedian Chris Tucker.

The hyper-kinetic, helium-voiced imp that ruined the last half of "The Fifth Element" with his squealing and screen-hogging, Tucker is a surprisingly good foil for Chan's tempered-yet-outrageous comedic style. But these two are no Murtaugh and Riggs, and something gets lost in the compromise, leaving this cop caper short on both action and laughs.

Chan is a Chinese agent sent to L.A. to help the FBI apprehend the Asian mafia kidnappers of a consulate's daughter.

Arrogant about needing any aid, the Americans tap Tucker -- a loose cannon (of course), wannabe fed from the LAPD -- to babysit and keep Chan out of their way, but the new partners go against orders (of course) and decide to rescue the girl themselves.

The picture follows an entirely predictable path while it plays heavily on culture clash gags and the physical comedy stylings of its two stars. But Chan and Tucker never fully mesh and some scenes in "Rush Hour" are tantamount to seeing a split-screen effect -- like neither of them know the other one is there and they're off and running in their own bit.

This is especially true of Tucker, who is essentially doing a caricature of Eddie Murphy in the "Beverly Hills Cop" movies, as he runs on at the mouth as he's wont to do and garners a few laughs from an arsenal of "it's a black thang" maneuvers. Chan gets in his obligatory kung-fu scenes, but doesn't have any of the spectacularly risky stunts his fans like to see.

Directed by Brett Ratner, who also teamed with Tucker for "Money Talks," "Rush Hour" is also pinched by its tiresome cliches (e.g. the eenie-meenie-miney-moe theory of bomb disarmament) and huge gaps in common sense. While these kind of problems are forgivable, even charming, in Jackie Chan's low-budget, badly dubbed Hong Kong movies, somehow they're much harder to excuse in American movies with enough money to hire a decent script doctor.