Harry Dresden's life finally seems to be calming down—until a shadow from the past returns. Mab, monarch of the Sidhe Winter Court, calls in an old favor from Harry—one small favor that will trap him between a nightmarish foe and an equally deadly ally, and that will strain his skills—and loyalties—to their very limits.

For once, the future looks fairly bright. But the past casts one hell of a long shadow. An old bargain has placed Harry in debt to Mab, the Queen of Air and Darkness—and she's calling in her marker. It's a small favor he can't refuse... one that will trap Harry Dresden between a nightmarish foe and an equally deadly ally, and one that will strain his skills—and loyalties—to their very limits.

And everything was going so well for once...