A few months after the Justice League was formed, it reunites following a series of attacks on coastlines around the world, carried out by a group from underwater. When Atlantis claims responsibility for the attacks, the Justice League intervenes, stopping the last attack led by Prince Orin/Arthur, who justifies the attacks by claiming that the surface attacked first, through the terrorist known as Ocean Master. The Justice League then acts on three fronts: Batman, along with Martian Manhunter, investigates Orin's claims; Hawkgirl, Green Lantern, and Flash confront the Atlantean forces on the surface; while Superman and Wonder Woman go to Atlantis, along with Orin, seeking diplomacy. However, things become complicated when Orm, Arthur's brother and current king of Atlantis, is revealed as the terrorist Ocean Master, responsible for the attacks on his own people, manipulating both sides into war in pursuit of more power. With the League's help, Orin manages to expose his brother, dethroning him for attacking his own people, but it's not over yet. Orm unleashes the Kraken beast as he and his supporters advance to launch an attack on the surface. The Justice League joins forces with Orin to confront him, stop the threat, and prevent war between the two peoples.
