It was a long strecth between books 3 and 4 for me. I read some reviews of the first 3 books to refresh my memory and I'm glad. Rowland includes references to the earlier books but it was helpful to have done a refresher. 
 Although a lot goes on, the first half of the book moved at leisurely pace then the action really picked up. When I looked back at the first half, there was a lot happening but it just felt leisurely and then events happens more quickly. Along the way, we get several mysteries complete with red herrings and twists; some romance, a few surprises, action and character development. I really like Eilahn, Kara's roomie and I hope we see more of her. We get answers to many questions and of course we get new questions. I enjoy seeing Kara puzzle things out and how her mind works. I think I'd like her if I met her in the real world. The ending was a surprise, quite a cliffhanger! I hope the wait at the library for the next one will be short!