Really, really well done romantic suspense. Wonderful growth on the part of the heroine (you need to read Deadly Fear before you read this one). You could see her confidence and feeling of self-worth grow from the beginning to the end.
And how interesting the way that Monica (heroine from book 1) was humanized throughout the book. Eden shows how even the strongest of people have doubts and hurts when they deal with serial killers all the time.
The only thing that keeps it from getting a 5 is that there were lots of times when I thought, "Really? You're getting it on now?"