In the last few years, the Red Planet has yielded up many new clues that life may have once existed there...and may even exist there today. There is now have proof that water once flowed on the surface, that Mars once had lakes, and that the frozen poles are mostly water, not carbon dioxide as previously thought. Mars has snow--an aurora--and lightning generated by dust storms. Most intriguing of all are the seasonal plumes of methane that just may point to bacteria living below the surface.

In the second episode, the directors learn their vision for the films is not always permissible by the U.S. government. Wyler is shocked by the racism he encounters against African American soldiers and refused to make a film recruiting black soldiers. Meanwhile, the films' racist depiction of the Japanese versus human depiction of the Germans causes worry for the War Department, which at that time planned to redistribute the Japanese-American population from internment camps into towns across the United States.

Could the source of the world’s deadliest viruses hold the secret to a healthier and longer life? Bats have a sinister reputation as potential sources for some of the deadliest disease outbreaks: Ebola, MERS, SARS, and most recently, the virus behind the COVID-19 global pandemic. Yet scientists are discovering new evidence that bats are biological marvels and may hold a key to longevity. They’re resistant to the diseases they carry and have freakishly long lifespans for their tiny size.
So, what’s their secret? And what else can we learn from their peculiar biology? From caves in Thailand and Texas to labs around the globe, the films meets the scientists who are decoding the superpowers of the bat.

For thousands of years, mankind has found comfort in its presence. It's been a lantern for nighttime travellers, a timekeeper for farmers and a location finder for sailors at sea. For some cultures, it's even been a god. It's the only cosmic body ever visited by human beings. From afar, the Moon's luminance has captivated us since the beginning of time. And a closer look at the beacon in the dark sky reveals an ever-present source of myth, intrigue, controversy and unsolved mysteries. The field of science may cast an empirical light on some things about the Universe, but lunar experts are the first to admit they don't have all the answers when it comes to our Moon. This episode explores the theories behind Lunar Transient Phenomena that have left scientists stumped for centuries; takes to the Canadian waters to see how the Moon effects our planet through tides; and dusts off some age-old myths and weighs arguments that without our Moon, humanity may not even exist.

We sure lucked out with Planet Earth. Blue skies, rolling hills, water everywhere. But our home didn't come like this out of the box. Earth was a real fixer-upper, and it took some seriously hard work to build this paradise. Nearly four billion years of renovation. Some tiny, some huge, to make this house a home. Creatures on Earth don't just live and die. They actually change the world around them.
The story of how for nearly 4 billion years, microbes, plants and animals have emerged and sculpted the planet's surface and atmosphere in the strangest of ways.

Visit the planet most like Earth. There is a discussion of what life on Mars would be like and about the life forms that could've evolved there