Third in the series. Armstrong gives some backstory but I think the setting is different enough that starting at the beginning would be better. There's sure a lot of action in this one but unlike the previous two, I was unable to suspend disbelief for this plot. It was just too hard to believe that the Council would send a serial killer to Rockton. They had to know the facilities aren't capable of holding someone for months at a time, and if they are taking money from the other residents to keep them alive, it sure seems counter-intuitive to send a known killer. I could believe Eric would act so naively but not Casey, but no, she's like a gullible 10 year old. Throw in a couple really unlikely predator attacks. The convoluted plot spirals out of control with all the main characters and the kitchen sink implicated in one way or another. So...I might try #4 just because I'm into the series this far, but I was pretty disappointed in this one.