This first book in the series is interesting but there are a few challenges. Most of the characters were fleshed out pretty well and there were quite a few plot twists to keep you turning the page. The pace was near perfect. What kept it from being rated a 4 was a somewhat stilted dialogue at times, especially between Susan/Sally and Quinlan. I often found it problematic to make some of the emotional shifts, which seemed to come out of the blue.Despite the above, this is an interesting story and one I'm glad to have read...enough for me to move on to the next in the series.