A new school year means many things for nine-year-old Phoebe Howell and her unicorn best friend, Marigold Heavenly Nostrils. They prepare for a school dance (lame!), meet new friends (ghosts and gnomes and goblins, OH MY!), and even experience a rare supernatural phenomenon called a Unicornado! In fact, sometimes things get almost too magical. Marigold's presence attracts pixies, talking birds, and a sphinx, turning Phoebe's house into a magical sylvan glen. And Marigold even briefly transforms Phoebe into a goblin!