Deep underground in Mineworld, a tribe of humans are slaves to the malevolent overlord Zygon, whom they believe to be their god. They have been told for centuries that their world is the only world and any attempt to mine to the surface will only lead them to Hell. Then one day while mining, Orin discovers the hilt of a sword with powers only he can unlock. The sword comes a message urging Orin to journey to the surface, saying that if he can find the blade of the sword he can set his people free. Upon escaping Mineworld, Orin teams up with the reluctant smuggler Dagg and his ship, Starchaser, to search for the sword's blade.