During a deep-sea salvage, Ling Qi accidentally obtained a mysterious compass from the old world that had not been recorded by the "Brain of the Abyss". Not only is the compass not affected by Haiyuan City's technology, it also points to an unknown coordinate. This discovery broke the lie that "Haiyuan City is the only hope for mankind". Chief Conceptor Karax sensed this threat and sent Purifiers to hunt down Ling Qi. During her escape, Ling Qi met Eve, a defected historian from the upper class. Eve believed that the compass pointed to the legendary "Second Ark" - another shelter left by the Atlanteans. In order to uncover the truth and find a new home, the two must travel through the three-story structure of Abyss City, evade pursuit, fight against the behemoths of the deep, and ultimately challenge Carax's ideological confinement of the entire city.
