This was an interesting book, but a frustrating one as well. The fantasy part works quite well, but there's a "murder mystery" part which doesn't. I hate it when an author explicitly says, through characters and story, that a character or group of characters can't be guilty, and then they are. That's just not playing fair with the reader. In this case, the authors state very clearly that certain entire races of beings CANNOT use magic. So, of course, one of them turns out to be a powerful mage, and the reader is NEVER given an explanation for:
1) Why everyone is wrong about said entire race being magicless
2) Why no one could detect said mage's magic
3) How that mage could damp down everyone else's magic in weird ways
4) How that mage LEARNED to use magic in the first place
There's also a romance story that just doesn't work. Two characters with very different backgrounds just randomly get the hots for each other. It felt really forced.
The overall grand adventure was much better, and the main villain was remarkably creepy, as well as the most forward-thinking villain you could imagine, literally planning a generation ahead. That story is why this book is worth reading.
The secondary story, about the townspeople being so easily stirred up against a pagan in their midst, felt a little forced, but unfortunately possible. I had trouble with the setup, and why she was there in the first place, since that was all before the start of the book.