I'll admit right away I didn't finish this, so my comments only apply to about the first fifth of the book. I loved the description--sounded right up my alley, mixing mystery with history and science and maybe a little fantasy. But I couldn't get used to the writing style, which was first person, but continually addressing another person so there was a lot of "you did" that or "you said" that, and it just felt really awkward, and as an audiobook, very hard to distinguish a dialogue "you" from a narratorial "you," so I was confused a lot. I also felt that the book was like an apple turnover with way too much crust and not enough apple, if the apple was the murder plot. Normally I enjoy a book that rambles and doesn't seem to have a particular destination, but the whole point of a murder mystery is to build suspense and lead to a conclusion. In an Alexander McCall Smith, he can riff on cake all he wants and I'm glued to the page. Ditto in Thrush Green and riffing on the flowers on a country walk, or how much the vicar dislikes the new kneelers in the church. These details are the whole point of the book, which is creating a world. Not so good when you're trying to tell a story, and your reader is frustrated because just when it seems that you're getting to the point, suddenly you have five pages rambling on about I don't even know what, combined with an overload of "had I but known" melodrama. So, maybe it was a great book. But I'm afraid I won't find that out.