Ludwig II of Bavaria, the supreme childish fantasist among kings—and one of the most harmless of all kings—is such an obviously magical, gaudy subject for the movies that many people may look forward with glee to Visconti's Ludwig. But it's well to bear in mind that though Ludwig is remembered because of the pleasures his candied-rococo follies give us, Visconti's follies are grimly humorless. Of the major filmmakers, Luchino Visconti is certainly the most estranged from the audience. Sometimes, in his films, the vital connection between the material on the screen and us disappears, and Visconti doesn't seem to notice or to care—he just goes on without us, heavily treading water. This happens for almost the entire duration of Ludwig, which is two hours and fifty-three minutes long. The subject is so juicy and frivolous that bravura pageantry on its own, without much drama, might...