Twelve-year-old Symphony Strange has had enough. Enough of the ‘gruesome twosome’ Phyllida and Suzette’s mean ‘tricks’ because they don't see her as being posh enough, enough of St Bartholomew’s School for Girls and most of all, enough of having no friends. With headteacher Mrs Grabbit and all the other pupils in the twosome's menacing grip, Symphony can’t see things ever changing. So she’s mega happy when she gets a new neighbour and best friend in the shape of Annabatya de Vole, who is also joining their year. Okay, she may seem a bit odd and is batty about bats, but Symphony thinks Annabatya is amazing and she totally is, at absolutely everything, which sends ‘the gruesome twosome’ into a meltdown. Promising trouble with a capital T, they threaten to snoop into Annabatya’s father’s top-secret work. Desperate to protect her new BFF, Symphony decides to play Phyllida and Suzette at their own game, but has she done more harm than good?