Bella, Gwen, and the Lost Boys have escaped to Alnwick Castle, but it is not the safe haven they hoped it would be, for the "cure" for the Horologia virus has mutated into something even worse--so the Duchess Alyssa and Maddox Hadder set out searching for the virus's origin, an extinct poisonous apple, supposedly from a tree at the center of a labyrinth hidden deep within Germany and guarded by monsters.