Betrayed by his own subjects, Aquaman and the League fight to save Atlantis, the world, and Aquaman's own son against his half-brother Orm's coup.

After Aquaman frees Solomon Grundy, Hawkgirl and the Justice League are convinced that the Lord of Atlantis has gone rogue. But when the trail leads them to the mysterious Dr. Fate, they discover there is more to this strange partnership than meets the eye.

With the initial ritual destroyed, the League, Fate, and Grundy must travel into the dimension of the Old Ones while Aquaman fights the invaders in the Earth realm.