The new film by Alfonso Cuarón is a dazzling piece of artful entertainment. It’s a sci-fi adventure, with a pair of stranded astronauts played by George Clooney and Sandra Bullock trying to survive a space-station calamity, and it packs a great deal of unexpected interest into what might sound like a relatively simple story. Scarcity of oxygen, suspension of the law of gravity, extreme physical isolation—they all heighten the stakes in the characters’ efforts to improvise self-rescue via the increasingly disabled remnants of their elaborate space-travel technology. Cuarón and company make wonderfully expressive use of the 3-D format on behalf of all of its main concerns. Both visually and dramatically, Gravity is about human beings struggling to get their bearings, in several senses of that word. Spatial and psychological disorientation recurs, but the screenplay by Alfonso and his brother Jonás Cuarón also nudges us toward perspectives on the dimensions of human identity, of purpose and self, and locale. Cinemark 14, Feather River Cinemas and Paradise Cinema 7. Rated PG-13.