在上一次试图击败海王（杰森·莫玛 Jason Momoa 饰）未果后，黑蝠鲼（叶海亚·阿卜杜勒-迈丁 Yahya Abdul-Mateen II 饰）依然不甘放弃为父报仇，誓要消灭海王。这一次，他找到了传说中的黑暗三叉戟，释放出古老的邪恶力量，比以往更来势汹汹。为了与之抗衡，海王向被囚禁狱中的弟弟奥姆（也是前亚特兰蒂斯国王，帕特里克·威尔森 Patrick Wilson 饰）求助，组成了出乎意料的联盟。他俩必须抛弃前仇旧怨，携手并肩作战，才能从即将到来的灾难中保卫王国，拯救家人，拯救世界。
Story follows an out-of-work steel worker as he struggles to provide for his family and avenge his brother's death by fighting in a mixed martial-arts match against a dangerous opponent.
Debt-ridden pacifist Richard Fyre is propositioned to return to his abandoned mercenary ways by flamboyant zealot, Priest, to eliminate his international competition in exchange for a clean slate.
An isolated private investigator is convinced by a friend to come out of hiding to help find her missing sister, putting him back in reach by those who want his family dead.
