Daisy Wells and Hazel Wong are spending the Christmas hols in snowy Cambridge.

Hazel has high hopes of its beautiful spires, cosy libraries and inviting tea-rooms – but there is danger lurking in the dark stairwells of ancient Maudlin College. Two nights before Christmas, there is a terrible accident.

At least, it appears to be an accident – until the Detective Society look a little closer, and realise a murder has taken place.

Faced with several irritating grown-ups and fierce competition from a rival agency, they must use all their cunning and courage to find the killer (in time for Christmas Day, of course).

The fabulously festive fifth mystery from the bestselling, award-winning author of Murder Most Unladylike.