M. Night Shyamalan's encore to The Sixth Sense, a hard act to follow. But follow it he dauntlessly does, all the way to a mandatory Surprise Ending. At first the fearsomeness of the task seems to drive him to overdirection, a big show of being busy: a woozy camera for the 1961 prologue, a swiveling camera for a passenger-car conversation viewed through the crack between the next seats, an upside-down camera for the perspective of a child on the couch in front of the TV. But soon enough the camera calms down. And Shyamalan, given license by his previous success, again stakes out an unusual area in commercial cinema: moody, bordered on four sides by gloomy, grave, somber, and morose. The plotline, please understand, is as silly as can be -- a comic-book aficionado, nicknamed Mr. Glass for the fragility of his bones (fifty-four breaks and counting), comes to suspect that the sole survivor of a Pennsylvania train wreck is his human opposite, an indestructible superman destined to serve and protect -- yet Shyamalan betrays no awareness of, much less awkwardness or embarrassment over, any silliness. And in truth, the grip of the movie depends far less on narrative propulsion than on atmospheric muck. (At least, that is, until the psychic visions of the suspected superhero assume the place of the ghostly apparitions in The Sixth Sense.) That might explain why this movie is a bit less gripping than its predecessor, though not less unusual. Bruce Willis is again along for the ride, dragging his foot and enjoying not a single minute of it. With Samuel L. Jackson, Robin Wright Penn, and Spencer Treat Clark.