Having failed to defeat Aquaman the first time, Black Manta, still driven by the need to avenge his father's death, will stop at nothing to take Aquaman down once and for all. This time Black Manta is more formidable than ever before, wielding the power of the mythic Black Trident, which unleashes an ancient and malevolent force. To defeat him, Aquaman will turn to his imprisoned brother Orm, the former King of Atlantis, to forge an unlikely alliance. Together, they must set aside their differences in order to protect their kingdom and save Aquaman's family, and the world, from irreversible destruction.