Two children have gone missing in Herefordshire, and Peter Grant is sent out to check on a retired old wizard in the area, just in case he might be involved (or aware of something the regular police won’t ask him about). He finds Hugh Oswald, but he’s old, frail, and falls asleep very easily. He’s not aware of anything, and is a seriously poor candidate to have done anything. His granddaughter, Mellissa, is a beekeeper in a fairly big way, and there’s definitely something odd about her, but she doesn’t seem at all a likely suspect, either.
So, back home to London? No, with two children missing, Peter doesn’t want to walk away. He calls Nightingale to report, and also to ask permission to go offer his services to the local police.
The local police are not inclined to refuse an extra officer on the case, but they do have concerns. Does PC Grant have any reason to think there is any of That Weird Stuff involved? No, he just doesn’t like two children being missing, and he doesn’t have any pressing cases waiting for him in London. They go around the question a few different ways, but Peter assures them that he expects this to be as routine as a missing-children case can be, and he’s happy to do any job that will make him useful. He gets tagged as the assistant Family Liaison Officer for one of the families, freeing up an experienced local officer for the search for the missing girls.
But of course Peter’s venture out of London can’t be smooth and uneventful – or unmagical. He starts to notice signs of odd things going on with this case. The girls were in the habit of taking “night walks” when conditions suited. One of the girls had an “invisible friend,” a unicorn called Princess Luna. One of their cellphones is found, but it’s dead. Battery dead, is what the local authorities conclude. Peter asks to examine the phone, and it’s dead from the effects of magic performed nearby. The other girl, not the one with the unicorn friend, has an older half-sister who ran away years earlier, taking her baby sister with her–and something strange happened, that she can’t quite recall, but she went home taking her baby sister with her.
Beverly Brook, who should be in London, comes to Herefordshire – and gets kidnapped by a couple of local river goddesses, because she thought it would be simpler to swim, and trespassed in the process. Peter has to come and make nice to the river goddesses to get her out. Their relationship seems to have taken another step forward, and Peter is happy about that.
He’s not so happy that Lesley May has started calling him. They’re quick calls, from a burner. He has to log and report every contact, and his superiors have some hope of getting her to turn herself in. Peter doesn’t share that optimism, He’s soon using a a burner phone for the unavoidable contact with her.
Meanwhile, the missing girls case keeps getting weirder and weirder. There are carnivorous unicorns, a changeling, ghost trees, a forest with a convoluted history where strange things happen, and a faerie queen who is, well, think all your images of wicked elves rather than nice ones. There’s Harold Oswald, who though elderly, frail, and inclined to sleep a good deal, is more on the ball than Peter initially thought.
Peter learns some interesting things about Nightingale’s past.
And there is a major, dangerous clash in the forest.
Peter’s life is not going to be the same again.
There’s fun and humorous moments, too, but this is a book with emotional depth and major challenges for Peter.