I've only just started this.. 9% of the way through according to my Kindle. Having never read any of the other Mirror Universe novels, I was a bit worried that there would be a lot of references to things I didn't know about and all that usual stuff.. but so far everything has been written in a way that doesn't bore me with lots of exposition on the history of the books but doesn't leave me wondering who is who or what is what. I'm sure that there are characters that people who have read the proceding books would know better than I will.. but it's not like you are totally lost.