Oceans: What Lies Beneath - Episode 2

Gabrielle Walker explores why we know so little about the oceans that make up nearly 80 per cent of our planet. Gabrielle meets the oceanographers who have gone where so few have gone before - the deep ocean. They have made discoveries that the most imaginitive science-fiction writers would have trouble imagining. The deep ocean is the most unexplored part of our planet, and makes up more than 50 per cent of the Earth's surface.