The ocean is filled with giant, strange, and scary creatures such as whales, octopuses, and sharks—but the prehistoric megalodon was powerful enough to crush a killer whale. Other sea beasts of the past could hold their own against even the most mysterious of modern sea creatures. Sea scorpions had claws the size of tennis rackets. Tanystropheus used its long neck to catch fish from land. And Leedsichthys had as many as 40,000 teeth! What would happen if these extinct beasts came to life? Imagine prehistoric sea beasts chasing dolphins, fighting crocodiles, and hunting humpback whales—and learn all about the prehistoric creatures of the deep!