Pearl and Jodie are sisters. Pearl is the quiet, cautious, studious one. Jodie is bold and brash and bad - but Pearl adores her anyway. When their parents get new jobs at a fusty old boarding school, the girls have to move there and spend their summer holidays in the school with just a few children and staff for company. And when they arrive, things start to change. Jodie has always been the leader - but now it's Pearl who's making new friends. And when a tragic event occurs, Pearl realises quite how much she does need her big sister...