At the very end of East Africa’s Great Rift Valley, there’s a ‘land that time forgot’ – the rolling grasslands of the Luangwa Valley. As we travel through the seasons, we find the secret to this Eden’s great riches – the annual flood of the mighty Luangwa River.

In the far-flung tropical Pacific, around 1,000 km from anywhere, lie the Galapagos Islands. On a journey from the lava ramparts of its coast to its fiery heart, we’ll discover how this place became one of the most important areas of biodiversity in the world.

At the far tip of South America, lies a magical realm that seems frozen in time. Known as ‘the end of the world,’ this is Patagonia. Voyaging from high Andes to coastal fjords, we’ll learn that to survive here you have to be as extreme as the country itself – either specialize in one habitat or be tough enough to live in all.

In Southeast Alaska, there’s an ice-bound Eden. Home to possibly the richest temperate rainforest of all, it has the densest concentration of grizzly bears in the world. In a story that follows the seasons, we’ll see that the secret to its great abundance is nature’s greatest migration – the salmon run.