This story picks up and runs full throttle. There is so much going on. The characters have been constantly evolving and they are just trying to do what is right for everyone. At its base, this is a story about social injustice set in a dystopian setting. Really, you have two different things going on at the same time — trying to survive in what this world has become, and trying to get everyone to live together peacefully, while getting the word out as to what is really happening. Then there is the evolution of Rowena herself. There is so much build up as to what will happen on all of these accounts. There are many surprises along the way, too. I never saw what was coming next and could not put the book down.
The previous books should be read first since there really is no back story given to lead us into the current book. But the story is quite interesting and the characters are unique and complex. You should try this series.