The Underworld: Journeys to the Depths of the Ocean

For all of human history, the deep ocean has been a source of wonder and terror, an unknown realm that evoked a singular, compelling question: What’s down there? Unable to answer this for centuries, people believed the deep was a sinister realm of fiendish creatures and deadly peril. But now, state of the art technologies allow scientists and explorers to dive miles beneath the surface, and we are beginning to understand this odd and exotic underworld: A place of soaring mountains, smoldering volcanoes, and valleys 7,000 feet deeper than Everest is high, where tectonic plates collide and separate, and abnormal life forms operate under different rules. Far from a dark void, the deep is a vibrant realm that’s home to pink gelatinous predators and shimmering creatures a hundred feet long and ancient animals with glass skeletons and sharks that live for half a millennium—among countless other marvels.

Susan Casey is our premiere chronicler of the aquatic world. For

Throughout this journey, she learned how vital the deep is to the future of the planet, and how urgent it is that we comprehend it in a time of increasing threats from climate change, industrial fishing, pollution, and the mining companies that are also exploring its depths. The Underworld is Susan Casey’s most beautiful and thrilling book yet, a gorgeous evocation of the natural world and a powerful call to arms.