The Amazon is the last great unknown region on Earth, but what lies beneath the great river's surface? Join Mike de Gruy, Kate Humble and an international team of scientists and divers as they find out on an extraordinary journey deep into the heart of a dangerous and beautiful world. Venturing where no human has been before, some of Earth's strangest creatures including giant black piranha, six-foot long man-eating catfish, and oversized freshwater stingrays are filmed, many for the very first time.
