This is the story of an awe-inspiring coastline 4,000 miles long. From the cold, fearsome waters of Cape Horn, where brave rockhopper penguins overcome huge challenges to raise their young, to the far north, with huge elephant seals battling for position in the heat of the desert. Orcas ram-raid the beaches, grabbing seal pups to feed their young. People gather the sea's bounty too, but these shores are not for the faint-hearted.

• Santiago Cabrera