The Grand Adventure of Cate R. Pillar is the personified life of a caterpillar as she plays with her friends, plans an adventure that she expects her friends, Wooley Worm, Priscilla and Druscilla the lady bug twins, and Paul Preying Mantis, to participate in, but when they don't, she decides to go alone. Many things happen to her on this journey including turning into Madame B. Utterfly. She reunites with her friends in her different form. With her new freedom of flight she is soon off to see what waits over the fence. In Halcyon Park she meets Prince Swallowtail and they have an adventure of their own. Halcyon Park really existed, as did Grandpa and Grandma Strawn.