There was a time, about 2 1/2 years ago, that a third Chronicles of Narnia movie was not a safe bet. Disney pulled up stakes while licking its corporate wounds from a bad showing by the second film, Prince Caspian. When The Voyage of the Dawn Treader wound up at Fox, the idea was to aim for the middle of the road instead of featuring, as its predecessor did, lots of violent swordplay. The resulting film does not provide fans of C.S. Lewis’ books much hope for the future. It’s tepid, maybe even gun-shy, and the only real positive is young Eustace Scrubb (Will Poulter), a cousin of the universe-hopping Pevensie children, who many viewers might find totally unbearable. Without Eustace, however, this trip to Narnia is a non-starter, lacking energy, polish, a visual style and that sense of wonderment that a good fantasy film is supposed to offer.