(The Dresden Files, Book 3)
But in all Harry's years of supernatural sleuthing, he's never faced anything like this: the spirit world's gone postal. All over Chicago, ghosts are causing trouble--and not just of the door-slamming, boo-shouting variety. These ghosts are tormented, violent, and deadly. Someone--or something--is stirring them up to wreak unearthly havoc. But why? And why do so many of the victims have ties to Harry? If Harry doesn't figure it out soon, he could wind up a ghost himself . . .