Now available in hardcover-the fourth novel in the New York Times bestselling Dresden Files series.

Harry Dresden's faced some pretty terrifying foes during his career. Giant scorpions. Oversexed vampires. Psychotic werewolves. All par for the course for Chicago's only professional wizard.

But in all Harry's years of supernatural sleuthing, he's never faced anything like this: the spirit world's gone completely 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.