Will Smith confronts his fear of nature on powerful white-water rapids in Iceland. "Over five expeditions, I've followed explorers into situations that were straight-up scary. It was worth it to discover the Earth's wonders. But your boy was tripping more than once. Because when I see wilderness, you know, nothing but nature, I get nervous because I don't understand it."

There's a killer lurking in our galaxy, a star ready to explode into a supernova. Seen from Earth, a supernova in the Milky Wave would have a terrible beauty. But for us, it could be fatal. In a few seconds, it can release as much energy as the sun will over its entire lifetime. It could be anywhere. It is nearly impossible to predict where and when the next supernova will happen. The hunt is on to find the next supernova before it finds us.

On the trail of tiger sharks in the Pacific, Will Smith explores the power of smell. Sharks have a sense of smell that's hundreds of times more potent and accurate than that of humans. An enormous part of their brain is dedicated to smelling, to finding their way through the vast expanse of the ocean.

Each night, across the planet, our cities illuminate the darkness. Their lights burning brighter than ever before. And whilst we're asleep, animals are making the most of this new neon landscape. The sunset in Los Angeles, Chicago, and Toronto creates worlds of opportunities for the cleverest animals willing to take the risk.

The Hale-Bopp Comet is passing Earth and rumours of a mysterious object following the comet could mean the sign that the Heaven’s Gate community could be looking for. With plans for the Exit, the group members begin saying goodbye to the world. In the aftermath of the suicides, the world and the surviving former followers react.

The last episode of the series showcases Africa, home to the greatest wildlife gatherings on earth and vast ecosystems. It delves into the lives of intelligent chimpanzees using tools in Ivory Coast, and the diverse cichlid fish in the Great Rift Valley's lakes. The film also explores the survival strategies of animals in the Namib Desert, including the brown hyena and the aardvark.
But even in this land of plenty, wildlife faces huge challenges. Crucially, it is addressed the impact of climate change and human activities, highlighting the plight of endangered species like the northern white rhinoceros and the decreasing populations of elephants and cheetahs due to poaching. However, it also offers hope, illustrating successful conservation efforts like the recovery of the mountain gorilla population in Virunga National Park.
The documentary is a vivid reminder of the richness of African wildlife and the urgent need for conservation efforts to preserve our planet's biodiversity.