My Thoughts: While not quite as engaging as the previous installments it still held my attention long past the time I should have gone to bed.
What Worked: I liked the introduction of demons and the Aedh beings in this book. Although we didn't get a whole lot of information about either it was nice to see something other than weres, shifters, vampires and lab creatures. The introduction of an interesting wolf shifter added to the cast of characters nicely and the bane of Riley, Sal, provided a measure of comic relief that the series needs to counter it's darker side. I thought the plot thread of Riley's investigation into the mutilated corpses was well done but a little less primary than I'd have liked.
What Didn't Work: As always I'm going to add the sex to what didn't work. The beginning had Riley acting like a petulant child after a tiff with her main squeeze. When she didn't get her way she responded by running to her second choice to hump like bunnies (or werewolves as it were.) I thought this was pretty ridiculous and immature. So far Keri Arthur has not fully convinced me that her werewolves HAVE to have sex...I concede that they do during the fully moon phase but the other 3 weeks Riley should be able to keep herself under control. She doesn't WANT to though. In addition to the sex I just didn't feel that there was as much action as in previous books. The mystery/thriller plot thread took a back seat to the sexual (dare I say perversions?) aspect. Mostly because the sadistic nature of the killer/s tied in with BDSM. So with so much sex and/or sexual situations I had a harder time setting them aside as I did with the three previous installments. Also, even though there was some recap on what happened in previous books, I don't think enough information was given to allow this book to stand alone or to be read out of order. Since I'm reading the books in order this wasn't an issue for me but as a reader, I should have the option to read a book in publication order or to just grab one off the shelf and start reading without worrying that things won't make sense. I really believe that if I'd started with this book instead of Full Moon Rising I'd have been lost and refused to read any more in the series.
In a Nutshell: With some positives and some negatives the book balanced out to an average read. However, I'm still enjoying the series and am looking forward to continuing on to the next one. I would recommend to new readers that they not start out with this book though. I'm finding with continuing story lines from book to book and not enough of a recap on past happenings a new reader would not find this book as enjoyable as I did. Read them in order people!