When the apocalypse hit, Alan Clifford sacrificed his lifespan to shelter humanity in an underground bunker for 30 years. But after peace seems near, he is betrayed by his adopted daughter Cindy Clifford and Chelsea Mason, who forge fake surface footage, incite the masses, and send him to the gallows. Believing their lies, humanity destroys the bunker and rushes upward—only to fall into a trap set by giants. As slaughter begins, Alan, now a master of mecha tech, must decide whether to save them again.
