It's a rainy day at playschool and the children can't go outside. Caillou makes up a funny story about a superhero who makes the rain stop - it's Super Caillou! He tells the story to Jeffrey and Jason, and Miss Martin suggests he make his own storybook. She writes the story down and Caillou draws the pictures. By the time Mommy comes to pick him up, Caillou has his very own book to show her!