More than two centuries after World War III poisoned the planet, the last bastion of humanity lives on massive floating ships circling the globe, searching for a habitable area they can call home. The aging and outdated ships have mostly long since crashed back to Earth. The only thing keeping the last two ships in the sky are the Hell Divers men and women who risk their lives parachuting to the surface to scavenge for parts that the ships desperately need. When one of the last ships is damaged by an electrical storm, the Hell Divers team is sent into a hostile zone known as Hades. However, down there is something far worse than the long-mutated creatures discovered during previous dives something that fundamentally threatens the more fragile than fragile future of humanity…