In this fifth installment of Mercy Thompson series, Mercy is happily mated with the alpha of the wolves, Adam Hauptman but her status in the pack is being threatened from the inside. In the previous novels, Mercy had borrowed a book from Phin, a fae whom owned a bookstore and had helped her on various occasion. However, when Phin disappeared with the only clue is within the book she held, things went awry for Mercy. On the other hand, Samuel is beginning to become emotionally destructive from the inside that he couldn't be in his human form without feeling suicidal. For werewolves, this usually the first sign for the wolf to overpower the humanity which resulted in full on cannibalistic psychopath. 
 Mercy does have her plates full in this book and although I do enjoy the solemn dramatic mystery acts in this book, it does get dysfunctional when you try to rationalize what Briggs try to expose with this book. But I do think that Mercy Thompson's story as herself was beginning to thin out like Sookie Stackhouse did. She seems to be a guest actor in this book instead of moving the plot. She just go on with the flow and things just happens to her with a rather small connection that ties her up with everything. I do think the alpha thing within the pack was forced, I know it works lovely with the storylines but I just felt Alpha & Omega is much better purview on the werewolf world than Mercy Thompson series. 
 I do wished Samuel's story would worsened as a cliffhanger at the end of the book with the revelation of Silver Borne at the end. It does feel like the author is trying to find an easy way out of the failing love triangle. Samuel deserved a full on graph storylines than just a subplot. Sorry Mercy, you're quite boring in this book and I'm not sure I will read 'River Marked'. Except maybe for more Samuel's subplots.