Assembled in 1004 B.C. by Rama Khan noble protector of Jarhanpur, the Ancients were the world's greatest superheroes of prehistory. The team was brought together to battle - as prophesied by Gamemnae, High Priestess of Atlantis - a "seven headed hydra" that would lay waste the earth.
Instead of a hydra, the Ancients fought and killed the Justice League of America, who had traveled back into the distant past to find their lost teammate Aquaman. The evil Gamemnae had duped the other Ancients to fulfill her schemes of conquering the world by preventing Atlantis from sinking and so changing the course of history. Meanwhile, present day Earth was threatened with disaster as every drop of water was drawn into the reservoirs of Atlantis, as it was raised from the depths of the ocean. To save the modern era, Batman called upon a roster of replacement heroes to go back several millennia and thwart Gamemnae's plans. The JLA revealed her treachery to the Ancients, and the heroes of two epochs joined forces to save past and present.