Changes, the last book in the series, ended on a bit of a cliffhanger. Specifically, the main character was shot and died. 
 Well, this is Dresden, so it's not like a little thing like death is going to stop him. He's back in Chicago for Ghost Story, kicking ass, solving mysteries, saving the world... only, this time, he's a ghost. 
 It's an interesting premise. The "ghost comes back to solve his own murder" thing has been done before, but you don't see it too often with the main character of a series, over a dozen books in. 
 And it was good to see Dresden have some new challenges for a while. He's always so powerful that he just blasts through enemies, but in Ghost Story, he can't. Suddenly, he has to sneak around and let others do a lot of the direct action. And Butcher makes a big deal of this - having Dresden note over and over again about how his perspective has changed, and how he can't just kill the enemy henchmen anymore because they can't kill him, so he'll have to find another way. It was a little preachy, but this is Dresden. 
 The action and pacing are as exciting as ever, and I did enjoy all the new discoveries Dresden made about the magical world now that he got to see it from a different angle. 
 My only problem with the book (other than the Catholic priest with a KJV on his nightstand - what was that about?) was that nothing that happened actually matters in the long term. His brief interlude as a ghost (no spoiler tags because of course Dresden isn't really dead) is all about revisiting the repercussions of his choices in Changes. Which fits with the ghost motif, but leaves us with a book that doesn't really advance the plot. Two baddies come back and are defeated, but we'd thought them both defeated anyway so it's not like any plotlines are resolved. We get to see the changes in Dresden's allies, but that could have been divulged differently, and in the next book. And while dying is a pretty big deal in character arch terms, it gets taken back at the end so what was the point? 
 Overall, the book felt a bit like a filler episode. Not that I'm complaining, per se, since Dresden is my filler reading when I need something light and fun and exciting. But it would have been nice for there to have been more long term meaning to the events of the book.