It's getting to be really hard to say anything meaningful about these books without giving massive spoilers for the earlier parts of the series, so I'm not even going to try.
Suffice it to say that it's another splendidly frenetic chunk of Harry Dresden's exceptionally eventful life in which he has to cope with multiple people (and other things) who want him dead (or worse) and to stop Bad Things Happening to himself, his friends and the world at large.
Excellent. Looking forward very much to the next one.
(*that's how it's spelt on the cover of my copy)