Nothing can stop the mighty Mega-Shark; not even the colossal sauroid in Mega Shark vs. Crocosaurus (2010). This time, the apex predator of the ocean wreaks havoc in the Port of Alexandria in Egypt; but, the U.S. Navy and the engineer, Jack Turner, have come up with an ambitious solution to this devastating problem: an AI-powered, autonomous shark-like submarine named the Mecha-Shark. Now, for the first time in a long while, humankind has an all-powerful champion on its side to crush the underwater menace; however, after a disappointing first encounter with the living terror of the sea, man's creation and Megalodon engage in battle, threatening to level Sydney. Can Jack find a way to avert the ultimate battle between Mega-Shark and Mecha-Shark?