Ida has to move house. Away from her home, her school, and above all – away from her friends. She finds life difficult in her new class. But one day their teacher, Miss Cornfield, announces that every child in the class will get a magic animal to accompany them. And the two outsiders, Ida and Benni, are the first to receive their new companions, who are supposed to be friends for life. Ida is allocated the fox Rabbat, while Benni gets a tortoise called Henrietta. It's not just that these magic animals can speak; they also have their very own individual characters. Henrietta may be rather slow on her feet, but she's almost 200 years old and very wise, while Rabbat is both sharp and funny. With Rochester at her side Ida suddenly becomes very popular; everybody wants to be her friend. Benni remains an outsider. But at least he can take Henrietta skateboarding and share his passion for pirates with her. And school becomes exciting in other ways: things keep on vanishing – a school thief must be at large! Wild suspicions begin to circulate, and the thrilling search for the criminal begins.