In the depths of the world's oceans, two ancient and powerful civilizations—Atlantis and Talokan—exist in secrecy, thriving in isolation and guarding their domains fiercely. When a fateful scouting mission into the Puerto Rico Trench ends with the brutal deaths of several Atlantean explorers, Atlantis’ King Arthur Curry (Jason Momoa) seeks to defuse the rising tensions with diplomacy. But his attempts are met with violence, as Talokan’s ruler, the enigmatic and unyielding Namor (Tenoch Huerta), is deceived into believing Atlantis is preparing for war.
What begins as skirmishes between these two mighty nations spirals into a confrontation of kings when Arthur and Namor engage in a trial by combat to determine the fate of their people. Yet, as their battle rages, a sinister conspiracy comes to light: Attuma, Namor’s trusted general, and Orm, Arthur’s exiled half-brother, have been orchestrating the conflict to seize power for themselves.
Forced to set aside their animosity, Arthur and Namor join forces to confront a rebellion threatening to consume their kingdoms. With the oceans on the brink of chaos and the surface world poised to exploit their weakness, the two kings must unite their armies in a spectacular battle that will determine the fate of their civilizations—and the fragile peace between their worlds.
