At the water’s edge a brave group of male penguins gather, preparing to make the dangerous journey ashore. With many threats ahead, there is safety in number and these petite penguins have important business to attend. It’s time to breed and they must find a burrow before the females arrive.

New Zealand’s West Coast is like nowhere else on Earth. From glacier-covered mountains to rain-drenched native forests to rough frigid seas, the landscape defies belief. Isolated from the rest of the world, this strip of almost untouched wilderness hides a host of endemic animals.

In New Zealand, two wild fortresses protect the vulnerable native animals: one a remote island protected by a moat of saltwater, the other a hilltop citadel surrounded by a predator-proof barrier. This is the story of these delicate sanctuaries and the life that thrives within them.

Spring on New Zealand’s east coast is a time of promise for the New Zealand Fur Seal and the Norther Royal Albatross. They’ve returned to their land to breed. But harsh terrain, fickle weather and hungry predators will conspire to make lives difficult for them. Only the strongest will survive to carry forward their legacy.

New Zealand’s isolated islands are famed as an unusual paradise, home to a variety of unique wildlife. Best known for its flightless birds, ancient reptiles and coastal mammals, a closer look reveals another world...