S1, E2: Spring begins in the sub-Antarctic islands with petrels searching through the snow for their nests. Elephant seals return from the sea and fight for supremacy over their harems, while five million Macaroni penguins battle through the crashing waves of South Georgia to court and breed. Further south the spectacular time-lapse sequences reveal a continent only just being freed from the ice trap. With the aid of remote cameras, there is also rare underwater footage of the hardier penguins as they venture far south to reach their traditional breeding grounds.