Oceans: What Lies Beneath: Part two

First aired in 2009. The deep ocean remains one of the least explored parts of our planet, but wherever scientists have been, in these dark, cold, inhospitable environments, they have found breathtaking and varied life.

Gabrielle Walker meets the scientists who have ventured where so few have been before, and finds out why NASA have taken such an interest in life in the ocean abyss.