Kathy notices Horton the Elephant and ends up in a jungle. She reads "Horton Hatches the Egg". The Cat in the Hat appears, and explains to her about Seuss in the 1920’s. Kathy then wanders into "The World of Advertising". The Ad Man and the Ad Woman explain about Dr. Seuss in the advertising business. The room rocks and Kathy is transported to Mulberry Street where she meets Marco. She helps Marco come up with a story to tell his father after he walks home from school.