Coral reefs are believed by many to have the highest biodiversity of any ecosystem on the planet. A lot of the life found here can seem very alien at first, they occupy less than 1 percent of the ocean floor but yet are home to more than 25 percent of all marine life. Warm water reefs typically come to mind when thinking of the Pacific Ocean and the Caribbean Sea, these reefs are very well known but they don’t just occur in warm waters.

Coldwater reefs are an enigma their secrets shielded by the dark ocean depths. Divers have explored all the worlds warm shallow water reefs their coldwater cousins are for the most part out of reach. How can coral which loves the light exist in such darkness? At 4000 meters beneath the surface what exactly is happening in these icy waters that we can’t see?

In some of the oceans coldest, darkest depths there are reefs that are thriving. They are formed by icebergs as they slide across the sea bed, leaving behind the perfect foundations for coral to build upon. Hidden from view, these reefs crisscross the planet from the deepwater tropics to the freezing Arctic. Many of which have never been explored by humans.

Once the surface of the moon was more familiar than the deep ocean but that is now changing. We follow a team of international scientists as they probe this alien world, from the ice edge of the North Atlantic to the west coast of Africa where the Sahara meets the sea they spy on the world beneath and are amazed by what they find.

In this one hour special, we are brought into this alien environment and discover for ourselves a strange, hidden world that is simply abundant with life, ranging from the weird to the wonderful.

Directed by: Gregor Truter