This is the (currently) last of the Sherlock books in the Elemental Masters series. Sherlock is officially still dead, as is Mary Watson, but John Watson and Sarah and Nan are trying to carry on some of Sherlock’s investigations where they can.
This story ends up being a mash up of “Hansel and Gretel” and the Hound of the Baskervilles (only locationally in this case – we find ourselves in Dartmoor). I really like how “Hansel and Gretel” got worked in here – the children we focus on are part of a desperately poor family, and it’s not a wicked stepmother that’s thrown them out. It’s their exasperated mother, after they’ve managed to waste the only food in the house, that was meant for dinner, through their hijinks. She’s sent them out to forage, because at least that way, they might get more food. Instead, they find their way to a lonely cottage on the moor where there are other children imprisoned.
They come to the London contingent’s attention when the mother writes to Sherlock, not realizing he’s “dead”. Coincidently, Sherlock is also involved, in a case that is seemingly not related, but of course turns out to be. It’s a fun story and a good twist on the fairy tale.