In a matter of days, the world will change. Billions of lives will be wiped away in a final, desperate search for the Child of the Faceless Ones - she who is destined to bring about the return of humankind's ancient overlords.

To prevent this, Skulduggery Pleasant and Valkyrie Cain have one last - terrible - option: the assassination of Damocles Creed. With protests stirring in the magical city of Roarhaven, with riots and revolutions on the horizon, Valkyrie must decide who she wants to be: the hero who risks everything for a noble ideal, or the killer who sacrifices her own soul for the fate of humanity.

The decision must be made, and time is running out.