Nintendo video game perennials Mario and Luigi come to life as plumbers who are thrust into a parallel dimension peopled by the descendents of dinosaurs. It seems that the meteor that hit the earth 65 million years ago (in Brooklyn, no less) didn't kill the dinosaurs, but hurled them into a world in which they have developed into a species of intelligent humanoids. And it is up to the Luigi brothers to save Princess Daisy, and life as we know it, from the megalomaniacal Koopa, who wants to merge the two dimensions and rule the world that will result.