Until now we've only touched the surface... The BBC spent five years and $10 million to produce this landmark exploration of the ocean, a world we know less about that the moon. We go further out and deeper down to show you things that have never been seen before. "The Blue Planet: Seas Of Life" reveals the sea and its communities at their most fearsome and alluring. "Open Ocean" - In the immense space of the open ocean the sea bed is a straggling five miles below the surface and the nearest island is over 300 miles away. Yet here live many of the most spectacular predators in the ocean. Marvel ads you experience ruthless and beautiful battles between hunter and prey. "The Deep" - A place of mountain ranges, perpetual night, pressure extremes and cold.... and the weirdest life forms on pour planet. Dive to the depths of the ocean, an eerie world where predators with teeth so large they can't even close their mouths, chase bioluminescent creatures of the deep. Discover the spectacular smoking chimneys of the hydrothermal vents. Go deeper down than you have ever been.