Rush Hour 3 is a half-hour of brilliance, preceded by an hour of dreck.
That's a roughly comparable dreck-to-brilliance ratio to the first two Rush Hour movies, I guess, and par for the course for Jackie Chan's Hollywood films (and a fair number of his Asian ones). It's just that the earlier Rush Hour movies are hit-and-miss throughout, whereas Rush Hour 3 is basically non-stop missing for an hour, saving all its hits for the end.
Fans of Chan's unique brand of action comedy could almost—no, I actually recommend that they do—buy their tickets an hour or so after showtime and stroll in to catch the last third of the film. What with pre-show trailers and advertisements, you don't have to worry about missing any of the good stuff. And if you stick around for the end-credit outtakes, with the usual assortment of flubbed lines, botched stunts and horsing around, you'll probably see all you need from the first hour. Enough to piece together bits of the plot, such as it is, that might not be clear from the third act. Definitely enough to get a sense of the crudity of the first two acts, in case you had any doubts about the prudence of skipping them. That the outtakes are funnier than the rest of the film goes without saying.
Not that plot points are a major concern in a movie like Rush Hour 3, which is even more shapeless and haphazard than its predecessors. In the first two films, LAPD Dectective Carter (Chris Tucker) and Hong Kong Inspector Lee (Chan) took turns being the fish out of water: First Lee came to Carter's LA stomping grounds, then Carter went with Lee back to Hong Kong. Now the boys take their odd-couple buddy-movie schtick to Paris, so they can both be the fish out of water. (You would have figured this ...1