Mab has traded Harry's skills to pay off a debt. And now he must help a group of villains led by Harry's most despised enemy, Nicodemus Archleone, to break into a high-security vault so that they can then access a vault in the Nevernever.

Problem is, the vault belongs to Hades, Lord of the freaking Underworld. And Dresden is dead certain that Nicodemus has no intention of allowing any of his crew to survive the experience. Dresden's always been tricky, but he's going to have to up his backstabbing game to survive this mess...