Britain is overrun by the Undead. Two sisters join forces with a team specialised in the Arcane. Their mission, to save humanity by finding and destroying the Necromancer, a powerful being who controls the Undead and raises hell on the world of the living.

On the night before Christmas Santa's scary helper Krampus traps the defiant 11 year-old Lyra in his magical bag. Here Lyra encounters the mysterious Keeper, who sends on a dangerous quest in order to win back her freedom.