This note contains spoilers for the book.

Anna Pigeon is now workin at a park on the north shore of Lake Superior (so she's in Michigan, but connected by land to Minnesota). She's got newly-minted dive and boat-handling certifications, too. Given how much a desert person she was, this seems a kind of extreme move. But I see how moving around parks gives a chance for a wide variety of settings for stories.

This one involves an extra body found in the engine room of an old wreck. Dressed in a period Captain's uniform, even. Deep enough that Anna really shouldn't be diving there, especially on her own (should one ever dive on ones own? I don't think it's considered safe in the diving community).

There's also quite a large and quirky collection of supporting characters (AKA suspects), including two pairs I kept having trouble keeping straight.

And she ends up in the hospital again; she really needs to be more careful.