When Richard Mayhew stops to help a wounded girl, it is the start of a nightmare journey into a parallel world that exists below the streets of London. The girl, Door, is on the run from two assassins.

Richard has fallen into the netherworld but wants his old life back. He must locate Door and the Marquis to do so. To find them though, he must pass through the most dangerous neighborhood in London.

The only person who can tell Door who killed her family and help Richard return to his old life is the Angel Islington. But where is he?

To find the key that will answer all their questions, Richard and Door must endure the dinner party from hell.

Richard and Door have won the sacred key for the Angel Islington. On their journey back, they descend to the depths of London, and come face-to-face with their worst nightmare.

With the key in his possession, only one person stands between Angel and his ambition.