During an unexpected stop off on Mondo Island, Carl Nelson, Susan Watson and Jiro Nomura discover a vast array of giant creatures, seemingly looked over since the time of the dinosaurs, living in close vicinity to one another on the small land mass. Among the creatures is the legendary ape King Kong, who, after taking a liking to Watson, defends the group against the threat of Gorosaurus. While Kong is entangled in a death struggle with the giant dinosaur, the trio seek to retreat while they still can. Their means of exit is cut off, though, by a Giant Sea Serpent patrolling the waters. Kong, after recently snapping Gorosaurus' jaw, arrives on the shoreline just in time to see the Sea Serpent approaching. The giant ape quickly intervenes, tossing boulders at the serpent in a bid to distract it. The large chunks of rock, although hitting their target, do little to shift the snake's attention from its prey. Kong quickly acts, rushing out to meet the serpent in close quarter combat. The fight is fierce, but short. The Giant Sea Serpent quickly constricts its body around the giant ape, but is no match against Kong who wrenches himself free and tosses the serpent back into the water, winning the bout.