Aquaman battles Superman when the Man of Steel must deal with an offshore threat on the former site of Coast City.
Aquaman v/s Superman ??
Aquaman is angry that the toxins and chemicals released from the upper world are being dumped on the ruins of Engine City. So, he says that the attack of the sea-monsters will be more frequent in the near future unless Engine City is retested and re-cleansed.
Meanwhile, a large Octopus-like creature attacks a harbour and almost ruins it. Two girls capturing the incident on a camcorder show the TV viewers a glimpse of Aquaman atop one of the tentacles of the creature, as if commanding it.
Superman sees the footage and rushes out into the sea to help victims at a harbour, only to be struck by another sea-creature. He falls into the waters and is seemingly drowning when Aquaman comes to his aid. Superman regains his senses and puts the blame on Aquaman. Aquaman corrects him, telling that he is not controlling the monsters. Both of our superheroes dive into the deep waters with Aquaman's pet dolphin, Porm.
They are surrounded by numerous sea-monsters and led to an underwater kingdom, ruled by a being named Kosnor. He informs them that the chemicals dumped into the oceans threatens the life of his subjects. He tells them of his imminent attack on New York City. Superman and Aquaman try to negotiate but are telepathically captured. They are tossed into a fossil's chest and imprisoned.
Aquaman hatches a plan, asking Superman to cover him while talking to Kosnor. He uses the hook of his left hand to grip an underwater rock and with Superman's help, breaks free of Kosnor's grip. He tells that escape was easy because Kosnor wasn't expecting an attack.
They head toward the surface and find numerous creatures traveling towards New York. Aquaman tries in vain to contact the creatures. Superman takes a chance and creates a whirlpool using super-speed. The creatures fall into it and are disoriented. They are directed by Aquaman to turn back. But Superman still feels that they haven't seen the last of Kosnor.