 Conrad and Sally Walden ( Spencer Breslin  (qv) and  Dakota Fanning  (qv)) are home alone with their pet fish. It is raining outside, and there is nothing to do. Until The Cat in the Hat ( Mike Myers  (qv)) walks in the front door. He introduces them to their imagination, and at first it s all fun and games, until things get out of hand, and The Cat must go, go, go, before their parents get back.