To be perfectly honest, there are not that many urban fantasy series that I am still reading - I went through a phase a while back of starting a number of them and the vast majority have fallen by the metaphorical wayside for a variety of reasons, usually having to do with how TSTL (too stupid to live) the characters are. This series, featuring Mercy Thompson, is one of the exceptions but it's very easy to fall behind and I realised recently that while I had books 7 and 8, book 9 is also due out this year!
I found the previous book in the series, River Marked, a bit of a disappointment though it still wasn't bad enough to stop me carrying on with the series, so I was pleased to see that I enjoyed Frost Burned much more. While the previous book was all about Mercy's honeymoon with her new husband, local alpha werewolf Adam, this book sees them separated some of the time since Adam and the rest of the pack have been kidnapped by rogue government agents. They want to force Adam to kill a politician, in the hope that this will cause outrage and shift public opinion against the werewolves, thus allowing more force to be used against them.
Since Mercy isn't at home when the mass kidnapping takes place, she ends up relying on the other relationships she has forged outside of the pack in order to help rescue Adam and the others. In general terms, this works out quite well though I think the overall storyline goes a little astray in about the last 20% of the book when the mastermind behind the plan is revealed. The overall body-count (dead and undead) in this book is quite high so if that's an issue for you, then maybe this isn't a series that will appeal.
The next book in the series is Night Broken, which I already have, so that means I'm then only one book behind!