Synopsis: One Ocean is an ambitious, provocative and stunning four-part documentary series that portrays the ocean more completely than ever before, revealing its awesome beauty and extraordinary power. The series explores how it is that the ocean holds the very key to all life within its silent and shadowy depths. In each breathtaking episode we bring to life a vast, interconnected ecosystem: from the diversity and significance of microscopic plankton, to the sleek power of the Ocean's top predators.