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.