Milo has been looking forward to a quiet Christmas holidays. Greenglass House, the old hotel where he lives in with his adoptive parents, is always empty over the holidays. But not this year. A steady stream of peculiar guests start arriving. They all have secrets, and he and Meddy decide to solve the puzzles.
There’s a lot of world-building here, but much of the story could take place without it. It isn’t until right at this end that this becomes overt fantasy, and everything is resolved a bit too quickly and easily. But before that, this is an interesting tale of Milo and Maddy working together, and exploit Milo’s deep knowledge of his house, to uncover an old dark secret.