In a deep-water submersible, Will Smith descends 3,300 feet to the bottom of the ocean, where even fewer people have gone than outer space. Along the way down, Will and explorer Diva Amon investigate how color is used in the natural world.

Thirty years ago, Will Smith was mesmerized by a photo of the incredible wildebeest migration across the Serengeti in a National Geographic magazine. Now he visits those same wildebeests and discovers an amazing survival strategy.

On the trail of tiger sharks in the Pacific, Will explores the power of smell. For humans, the sense of smell triggers deep memories and emotions, but it has an even more vital function in the animal world.

Will explores the Namibia Desert, where both the landscape and time seem to have stood still for over 50 million years. Will discovers that humans can only see a small sliver of what’s moving around us because everything on the planet is happening either too fast or too slow for us to perceive.

On a remote island in the Pacific, Will Smith descends into the heart of an active volcano to investigate sounds beyond human hearing. Will discovers that everything on our planet creates its own unique sound—even if we can’t always hear it.

For Will’s final journey, an ultimate challenge. He and polar explorer Dwayne Fields are dropped by helicopter in the middle of an Icelandic glacier.