ET Contact: They Are Here

In a studio setting, Stephen Hawking, Arthur C. Clarke and Carl Sagan (who joins them via satellite) discuss the Big Bang theory, God, our existence as well as the possibility of extraterrestrial life.

Featuring Michael Pollan and based on his best-selling book, this special takes viewers on an exploration of the human relationship with the plant world — seen from the plants' point of view. Narrated by Frances McDormand, the program shows how four familiar species — the apple, the tulip, marijuana and the potato — evolved to satisfy our yearnings for sweetness, beauty, intoxication.

A documentary on Al Gore's campaign to make the issue of global warming a recognized problem worldwide.

As Vladimir Putin continues his gritty reboot of the Soviet Union, he's getting a surprising amount of help from the party once led by Reagan. In this new special, "Jordan Klepper Fingers the Pulse: Moscow Tools," Klepper speaks to foreign affairs experts, possible Russian assets, and the Prime Minister of Russia's neighbor, Estonia, to find out whether Republicans have become the Kremlin's most useful idiots.

SNIPERS: BULLETPROOF deconstructs and analyzes the little known sniper events that have occurred when no other course of action was possible. The people who planned the takedowns, or pulled the trigger, share their techniques and bring to light the many factors that had to be considered in each mission: terrain, wind speed, temperature, elevation changes... all are critical to taking out targets considered bulletproof. A sniper has one chance, one breath, to rise to the occasion and save the day... if they miss, there may never be another opportunity. As these never told before stories unfold, the viewer also learns about the high tech gear each sniper carries on their classified missions.

Many geneticists and archaeologists have long surmised that human life began in Africa. Dr. Spencer Wells, one of a group of scientists studying the origin of human life, offers evidence and theories to support such a thesis in this PBS special. He claims that Africa was populated by only a few thousand people that some deserted their homeland in a conquest that has resulted in global domination.

Most people fully accept paranormal and pseudoscientific claims without critique as they are promoted by the mass media. Here Be Dragons offers a toolbox for recognizing and understanding the dangers of pseudoscience, and appreciation for the reality-based benefits offered by real science.

Darwin's great insight – that life has evolved over millions of years by natural selection – has been the cornerstone of all David Attenborough’s natural history series. In this documentary, he takes us on a deeply personal journey which reflects his own life and the way he came to understand Darwin’s theory.

Let There Be Light follows the story of dedicated scientists working to build a small sun on Earth, which would unleash perpetual, cheap, clean energy for mankind. After decades of failed attempts, a massive push is now underway to crack the holy grail of energy.

Is there a connection between bible stories of contacts with the gods and the modern day UFO phenomenon?

Of the Seven Wonders of the Ancient World, the Pyramid is the only one to survive. Many believe that even with our 21st-century technology, we could not build anything like it today. Based on the most up-to-date research and the latest archaeological discoveries, here is how the Pyramid came to be.