This was a really interesting read. It was interesting how the main character woke up in a body that wasn't hers all for the purpose of having to solve a mystery. There was a lot more to it than I first thought and I believe this is a book that you should read again just in case you missed something. Mercy, I love that name, is an angel who travels from body to body but never remembers where she was before. She is haunted by someone other than Ryan, a human boy she gets involved with.