Inside Cardia Beckford’s hazy recollections, she will be able to recall her father Isaac and the house the place she lives alone, feared as a monster by the townsfolk—for in her physique, she carries a lethal substance. Embedded in her chest by her father, the eternally beating coronary heart—also referred to as Horologium—has the potential to supply infinite energy. Nevertheless, it additionally makes her pores and skin destroy something it touches.
Many in London search the Horologium, together with the terrorist group Twilight, with whom Isaac is rumored to have shut ties. To acquire the Horologium’s energy, the British army forces Cardia to go away her residence as their prisoner. However on the street, she is whisked away by the gentleman thief Arsène Lupin, who says he’ll steal her coronary heart. Becoming a member of Lupin and his companions, Cardia begins a journey to find the reality behind Isaac’s reference to Twilight, her lacking recollections, and the Horologium inside her chest.