Hazel and Daisy go to Cambridge to spend Christmas with Daisy's brother, and, not incidentally, to meet up with the members of a rival detective agency. Mysteries and puzzles start piling up almost as soon as they arrive, keenly sniffed out by the veteran Detectives. Rivalry ensues, with Daisy unable to contemplate anyone else being allowed to take an interest in a mystery when the Detective Club is in town, though Hazel a bit more in favour of the spirit of co-operation. Before long, events take a serious turn and rivalries must be set aside in the interests of catching a ruthless and cunning culprit.

Another sparkling whodunnit with a knotty mystery and great characters and setting. Stevens does a great jb of balancing the innocence and youth of the detectives against the gravity of the crimes, not to mention the assumptions and heedlessness of the time and place against some more uncomfortable attitudes never far from the surface.