Barry Allen is struck by lightning, and as a result of this extraordinary event, the “Superpower of Speed” is born within him. But when he uses this power to travel through time and save his mother, the consequences are devastating. A world without heroes is born, and General Zod makes a menacing return. In the fight to defeat this tyrant, his only chance lies in the hands of a retired Batman returning to action, another Barry Allen from another timeline, and an imprisoned Kryptonian. This unlikely alliance is gifted with unique skills and knowledge, but the war against General Zod proves to be an immense challenge. Confronting their own mistakes and making difficult decisions, the heroes strive to restore order and save the world from collapse.