Another Space Cat spins into outer space. This time Space Cat's Martian wife and their two kittens join Colonel Fred Stone on a trip to a planet not unlike earth, except that its vegetation and animal life are behind our own in development and are, consequently, of a miniature size. But even midget dinosaurs can be dangerous when they are sharp toothed and abound, a fact which the two kittens learn for themselves when a pack of carnivorous Tyrannosauri all but devour them.