Selene, a mortal slave abused by War God Gaius, is taken to the Underworld by Hades, who finds her able to ease his cursed headaches, leading to their love. At their engagement, villain Freya frames Selene and tries to burn her alive, but Selene awakens as the reincarnation of Gaia, wielding the Earth's primordial power. She punishes Freya, reforms the War Domain, and marries Hades, while Gaius redeems himself by dying to protect her.