Sally and Nick are playing in the rain — and getting really muddy! So when the Cat in the Hat offers to show them how animals get clean, the kids are keen to find out. But can Sally and Nick really get rid of the mud by taking dust baths, like a sparrow? Or by licking themselves, like a lion? And where are they going to find an oxpecker to pick it off them, like a hippo has? (Besides, oxpeckers tickle!) Maybe there's a better way for kids to get clean? The Cat in the Hat knows all about that!