Michelle inserted chapters throughout the book which told the story of Mara's ancestors. This provided a history of the "superpowers" Mara and her friends possess. We also come to understand the motivations behind the research that is being conducted at Horizons, which shed some light on not only the characters' pasts and onset of their conditions, but also their future.
We eventually learn if Jude is "real or not real" and how he is connected to Horizons and Dr. Kells. I wish there could have been a way for Michelle to tell this story without using quite so much graphic violence. I read a lot of adult murder mysteries, so I am not opposed to violence as a whole. I just didn't think it was fitting for this series and specifically not when it was associated with Mara. It didn't bother me in the least when Mara "punished" a character with her powers, but it was a completely different story when she had to defend herself by traditional means.
The biggest disappointment had to be the lack of Noah throughout the story. I don't want to give away any spoilers, but he did not have nearly the presence that he had in the first two books. He is one of my favorite YA characters and is probably the sole reason I loved the first two books as much as I did. Without his presence, it felt like something was missing.
Overall, I felt like the story tied everything together and provided a satisfying ending. While it didn't live up to my 5 star hopes, it was still an entertaining story and a nice conclusion to the series. The last 100 pages was the saving grace for me. It probably doesn't take a rocket scientist to determine what must have occurred around this point, but I flew through the last 100 pages. If only the entire book could have been like that I would have given it 5 stars like the previous two.