I love the Mercy Thompson series. I like what she represents as our heroine of the series which is someone who can take care of herself, thinks things throught fisrt (for the most part) and is a truly caring person who is willing to help anyone out. 
 I find that the second book in the series is stronger than the first. We are dealing mainly with vampires in this one, and it's helpful that we've already had the introductions in the first novel. There are a couple new characters added (that will have a bigger impact later on in the series), but the main focus is still on those we met in the first book. 
 The threat this time is a vampire and unlike the first book I really felt like it was a true threat. The first book, I didn't think that the antagonist was a threat to more than a select group of people whereas this vampire really has an effect on everyone in its path. 
 I like the slow development of the relationship in this story. We see Mercy struggling with her feelings for both Samuel and Adam (although I always knew who I wanted her to end up with). I feel like it's obvious who she should be with but I think her dilemma on her emotions towards these two men is founded. She's not just dragging them along because they are both hot and she just can't choose (sigh!). There are occurrences in her past that give her pause (if you've read the first book these are introduced there). I think that it's handled in a tasteful way that doesn't have me irritated at the fact she needs to take time and figure out what's going to be good for her. With that being said, there are some really great sexually tense moments. Those are sometimes better for me than a love scene! 
 I think if you come into the series on this novel you should be ok, there's enough rehashing of past events to catch the reader up, but really if you do that you miss out on starting a great series from the beginning. 
 One of the things that slowed down the story a little for me was the "double ending". You assume that after the bad guy is defeated there will be a nice little wrap up and the end. Not here. Events unfold in a way that show that there is more than one bad guy to take care of. So I get all ready for the book to end (because that's where the story is taking us), but then there's more. It's not that I don't appreciate the direction the story went, but it broke it up a little for me therefore resulting in a slow moment. I do appreciate this form of storytelling because (unbeknownst to first time readers) the actions that take place in the "second ending" sets up the start of the next book. 
 Again, I can't praise this series enough. Please read it!!