Gong Li plus Chow Yun Fat sounds like some kind of superstar pairing, all right. Too bad it comes on the downslope of a precipitous decline in the watchability of director Zhang Yimou’s work. Gong is the Empress and Chow her Emperor in this grand soap-opera pageant of color and sound that seems born more from a desire to see how closely Chinese cinema can hew to the high digital standard set by the Lord of the Rings movies than by any honest attempt at storytelling on a human scale.