From the beginning of time, humankind has been fascinated, repelled, frightened and captivated by the great fish and mammals - both mythological and real - that live below the surface of the sea. In this book, Richard Ellis explores the world of man-eating octopuses, seductive mermaids, gigantic leviathans, sea serpents, and other legends of the deep. In a chronicle that takes the reader back and forth between mythology and reality, Ellis shows how the mermaid metamorphosed into the manatee; Leviathan became the whale; the polyp became the octopus; and the kraken is now known to us as the giant squid. He also investigates the natural history of these strange sea creatures and tells us, for example, why the giant squid is so rare, how the octopus has been misrepresented in history, the truth about the Loch Ness Monster, and whether the mermaid ever actually existed.