Really Rosie is a musical with a book and lyrics by Maurice Sendak and music by Carole King. The musical is based on Sendak's books "Chicken Soup with Rice", "Pierre", "One was Johnny", "Alligators All Around" (which comprise 1962's "The Nutshell Library"), and "The Sign on Rosie's Door" (1960). Sendak based the story on a demonstrative little girl who used to sing and dance on the stoop of her building, whom he observed while he was a little boy growing up in Brooklyn. The show follows a typical summer day in the life of the Nutshell Kids, a group of several neighborhood friends, including Pierre, Alligator, Johnny, and Chicken Soup from the "Nutshell Library" books, and Rosie and Kathy from "The Sign on Rosie's Door". Rosie, the self-proclaimed sassiest kid on her block of Brooklyn's Avenue P, entertains everyone by directing and starring in a movie based on the exciting, dramatic, funny (and slightly exaggerated) story of her life.