Caillou is excited about showing Rosie the ropes when they visit the library. During storytime Caillou imagines he's in the story, riding on a dolphin. Later he and Rosie argue over a book and accidentally tear it. He doesn't want to tell the librarian, but finally musters up the courage to do so. The librarian turns out to be very nice and he helps her fix the book. And Rosie gets her very own library card!