Neil Sinclair is no more. His transformation into Subject Zero has destroyed his former self and turned him entirely into a merciless warrior with an unquenchable thirst for power and vengeance. As he sets out to destroy all meta-humans who pose as threats to his dominance, it’ll be up to Kal to protect Lois from this monster seeking to exact revenge on the Lane family. But when Subject Zero tracks them down and their reunion is interrupted, Kal will have to become the Superman he is inside to take on the battle. The question is: can he do this in time to save Lois?