The expedition to film the creatures of the bottom of the Amazon River for the first time continues as the team head further up river and into the unknown. Mike deGruy and the team are on a quest to find extraordinary new species, including a fish that talks and the candiru - a parasitic catfish notorious for invading the human body. Meanwhile, Kate Humble heads deep into the jungle to film a rare freshwater dolphin and track down the elusive giant otter.