Young reporter-in-training Kate and her mouse-accomplice Rupert are on board a train, to visit Kate's mum in the Arctic. But as soon as the train departs, mysterious things start happening. A packet of ginger nuts goes missing . . .A collection of gymnastics trophies are stolen . . . And some ancient scrolls disappear . . . Fellow passenger Madame Maude seems the most likely culprit, until a surprising - and delicious - twist turns the whole investigation on its head. First in a witty two-colour chapter-book series about a bold young detective and a colourful cast of suspects, in a setting worthy of Agatha Christie.