Where is everyone? We have been listening for messages from outer space for more than half a century, and so far... silence, why? Are we truly alone in the universe? Or is everyone else acting like us and just doing a lot of listening? Maybe we need to be louder. Maybe we need to send more messages out there. But how do you write a letter to an extraterrestrial whose language and culture and biology and mind we have no concept of? And what do you say?
Given all of the unknowns about what they might behave, should we say anything at all?

In the third episode, the discovery of extraterrestrial life might face an impossible challenge: the physics of the universe itself; but using cutting-edge tech, experts might be on the verge of a groundbreaking find -- and the evidence could already be in hand.

The extraordinary story of Earth and why it is special and uniquely brimming with life among a largely unknown but harsh cosmic arena. It will be told by eight astronauts from their unique perspective of being away from Earth. In the first episode, Astronaut Chris Hadfield reveals the unlikely and unexpectedly interconnected systems that allow life on our planet to breathe.

'It's alive!' Since Dr. Frankenstein spoke those famous words, we've been alternately enthralled and terrified by the idea of creating life in the lab. Now, a revolution in genetic engineering and thrilling innovations in synthetic biology are bringing that dream—or nightmare, as the case may be—closer to reality. New tools allow researchers to use cells to create their own DNA and edit it into existing genomes with more ease and less cost than ever before.
Along with renewed hopes for treating some genetic diseases, there's serious talk of using the newest technologies to bring long-extinct animals back from the dead – like the team hoping to resurrect the woolly mammoth. Science fiction is quickly becoming science fact. Another daring genetic experiment to bioengineer animals could prevent Lyme disease. But the power to make life comes with deep ethical questions. What are the potential rewards—and dangers—of tinkering with nature? This films explores the benefits and the burden of risk surrounding the controversial new technology.

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.

From virtually the moment we're born, there's a story that's preached across cultures and continents. It's a familiar fairy tale, that finding one true love is the key to a fulfilled and happy life. As an adult, we're forced to reconcile the messaging on monogamy with one simple fact: humans are terrible at it.
What do biology, human history and the promiscuity of bonobos reveal about monogamy? Experts and everyday couples weigh in on shifting cultural norms.