The Main Man Lobo arrives on Earth to stop one country's indiscriminate slaughter of dolphins, just as Aquaman, Aqualad and Dolphin show up to free the captive Porm.
An angry Aquaman blows up in Strom's officer demanding to know how he has learned so much about him, which Strom cryptically avoids by giving him the location of Porm. Meanwhile Lobo having learned from a space dolphin of several being captured heads to Earth to make the culprits pay. Aquaman is then led to a research institute which now holds Porm, which Aquaman and the others decide the best plan of attack. Meanwhile Lobo has destroyed a ship, and is torturing one of the men for information on who took a space dolphin.
Aquaman and Aqualad then manage to tear a vault door off enabling them to enter the facility, finding Porm who urges him to assist the facilities owner from the fishing crew who seek to take back the dolphins to sell for meat. Finally Lobo gains the information arriving and begins slaughtering the fishing crew as well as attempting to murder the scientist believing him to be a part of the group, however he is saved by Aquaman's intervention, with the two battling. However, upon learning of Aquaman's connections to dolphins, meanwhile Aquaman holds the scientist as he dies in his arms. Outside Garth and Dolphin look on as Lobo as destroys the ship with a grade, as Aquaman sets up a trial for the surviving captain leaving his fate up to circling sharks as he gives the scientist a burial at sea.