Immortal Throne picks up immediately after the events of the main game: after the titan Typhon has been defeated, the Olympian gods hail the player character as humanity's hero, and decide that the human world can function without their protection. The player is transported to Rhodes, where a new wave of monsters has appeared: this is blamed by Tiresias on the player's activities creating strife in the Underworld, the source of the monsters. To discover the reason behind the attacks, the player must seek out the sorceress Medea, who sends the player to a region near the Pindos Mountains. Following a path into them, the player finds the path into the Underworld, where the dead are trapped in limbo due to the Judges of the Underworld no longer passing sentence on them. After the player defeats Charon and Cerberus, who have abandoned their original purposes, they head through Elysium. The player learns that Hades, god of the Underworld, is launching an attack on the living world now that the more powerful Olympians have left humanity unprotected. After trapping Hades' army in the Underworld, the player then defeats Hades himself. Persephone then appears, dubs the player "Godsbane" and declares that humans have earned the right to control both life and death.

Physical Game Disc on PC-DVD