When Lex Luthor tries to use cryogenic rays to cause a sharp drop in sea levels and create new islands that lead them, Superman and Justice League foils his plan. Because of an accident, Luthor is throwing a piece of ice and is presumed dead. In the 31st century, superheroes and adolescents Dawnstar Karate Kid visiting the museum where Luthor stood frozen for nearly a millennium and accidentally frees.
Luthor steals an ancient device that allow him to manipulate time and space. The convicted alongside Legion, Lex travels back in time to eliminate Superman, Batman and Wonder Woman before becoming superheroes.
For Aquaman, Flash and Cyborg, joined by Karate Kid and Dawnstar stake has never been so great. Justice League faces the biggest threat, the disappearance.