Viewers are transported to the Sub-Antarctic as the SEDNA IV sails across the Polar Front, an area where cold turbulent Antarctic waters meet warmer water from the north. This area represents one of the earth’s last great refuges for wildlife, with tens of millions of birds, fur seals and elephant seals returning each spring to breed after a winter at sea. The exceptional wealth of the Southern Ocean has always provided for amazing populations of unique species, but for how much longer?