Transplanted from her exciting life as an explorer's daughter, Freya finds herself miserable at boarding school. She hates the boring rules, the other girls are mean, and the headmistress is frostiness personified. When a bat removal expert is called in to deal with an infestation, Freya meets his irrepressible children - and makes friends at last. Together they explore the city, with particular interest in the grand exhibition showing priceless artefacts for the first time. Then the objects are stolen in a dramatic heist, and Freya is sure her new friends are responsible - but the true culprit might be closer to home . . .