UCL oceanographer Helen Czerski explores life in the ocean depths with a panel of deep sea biologists. They take us to deep ocean coral gardens on sea mounts, to extraordinary hydrothermal vent ecosystems teeming with weird lifeforms fed by chemosynthetic microbes, to the remarkable biodiversity in the muds of the vast abyssal plains.

Helen's guests are Adrian Glover of the Natural History Museum in London, Kerry Howell of Plymouth University and Alex Rogers, scientific director of REV Ocean.

They discuss the dramatic revelations made by deep ocean explorers in just the last forty years, and the profound connections that the deep sea floor has with life at the Earth's surface. They also consider the threats to the ecosystems down there from seabed mining and climate change.

Producer: Andrew Luck-Baker

BBC Inside Science is made in association with the Open University.