The bottom of the Amazon River is home to many of the strangest and fiercest creatures in the world. This is the first in a two part series following the high adrenaline adventures of a team of divers as they explore and film the depths of the world's greatest river system. It is the first time an expedition has ever attempted anything so ambitious and they discover an alien world, full of beautiful and bizarre creatures. Sting ray, freshwater dolphins, talking fish and the mysterious Jau are all to be found in the river's depths. Mike deGruy and Kate Humble lead the international team of scientists and divers as they search for species new to science and come face to face with the monsters of the deep.