Animated films have had a long tradition of depicting humans as marauding grotesques, but I can’t think of another one that took as jarring a turn in that direction as Happy Feet. For nearly 90 minutes, this gorgeously computer-animated musical follows the cheerful identity crisis of a young emperor penguin that can dance but not sing – and singing, in the movie’s world, is how penguins attract a mate. For its climax, however, our hero goes on a journey to discover why the fish have been disappearing from Antarctica and ends up in an Orwellian nightmare involving scientists and a zoo (the tots at the preview screening went silent, either out of confusion or horror).