When Maud's pet rat, Quentin, escapes in the middle of science class, it's the very last straw. Maud is transferred from Primrose Towers to Rotwood Middle School - to the delight of her teacher, classmates, and her perfect twin, Milly.
But what is in store at Rotwood? There's something strange about the pupils of Rotwood - everyone's dressed as though it's Halloween and the school's motto is "Because We Scare". Is 10-year-old Maud Montague monstrous enough for Rotwood?