For me, this was a very disturbing novel! It was, at parts, very confusing, but also had me on the edge of my seat at times. There were also times where I thought that the series was actually more of a saga of Amelia's journey toward being a whole, normal person.
In this book, the main couple is Brenda Banks and Nick Blackwood. Brenda was a very annoying heroine, constantly trying to interfere in the investigation to further her career at the news station. Her depression as a teenager that led into the feelings of not belonging/not being good enough as an adult also felt rather contrived, and all because she was adopted. However, this was resolved toward the end of the book, in a way that made sense.
Nick was also a bit annoying, what with the supposed demons from being raised by his father. It didn't make much sense as to why he could not be with anyone, all because of his childhood.
The ongoing saga of the experiment was very revealing, and disturbing. The serial killer in this story was a complete shock to me! I'm a bit interested to see how the experiment totally unravels!