There are two big "twists" in this book, and neither of them worked. Explanation beyond the spoiler:

The reveal that Anna's family members are actually dead was too, too obvious to anyone with common sense. Obviously she's grieving the entire time, and though she converses with her deceased husband, it's very unsubtly just a mental projection. I honestly thought that it was so obvious that it wouldn't even be a twist, but when it's "revealed", all of the plot halts as if it is some major world-shattering revelation. Dumb.

The second twist, the reveal that the teenage boy is actually the killer, has the complete opposite problem. There are literally zero signs of his devious nature throughout at all, so it comes completely out of nowhere. Poor plotting for a mystery.

Despite the flop twists, this book was actually pretty good. I gave it a pretty positive score because I did genuinely enjoy the characters and the pacing and the premise. Give it a try anyways!