Zachary Quinto explores the unpredictable and terrifying phenomenon of sinkholes to determine just what causes them. He visits a Florida man whose brother was killed when their family home was literally swallowed whole by the Earth as well as a series of sinkholes that are forming a series of caves right below the houses of a quaint suburban neighbourhood.
Whether they be a part of some biblical prophecy or further evidence of mankind's effect on our planet, he's alarmed to discover that all the same, they can strike anywhere in the world, at any time.

Space colonization is no longer the fodder of science fiction, it is becoming a reality. Examine the efforts underway to establish a human colony on Mars, including how they plan to grow food, recycle wastewater and introduce greenhouse gases to revive the red planet and make it more habitable for humans. Cutting-edge computer graphics are used to bring the universe down to earth to show what life would be like on Mars, and to imagine what kind of life forms might evolve in alien atmospheres.

Planets beyond our solar system are known to astronomers as exoplanets. They are at trillions of miles from Earth and yet, it might be possible to detect a faint signature of life in them. From the light of the stars they orbit that passes through the atmosphere of an exoplanet, it is possible to capture the chemical fingerprint of the elements in that atmosphere.
The fictional world Eden is orbiting not one star, but two. The light from its twin stars powers photosynthesis, pumping more oxygen into the atmosphere than in Earth, allowing life to thrive. Grazers are constantly alert to danger, because the canopy is home to predators perfectly evolved to live among the trees. In Episode 3, another topic are fungi and the role they could play on exoplanets. Ecologist Thomas Crowther talks about the role mycelial networks play in the Rothiemurchus forest in Scotland.

The white hole is a region of spacetime and that cannot be entered from the outside, although energy-matter, light and information can escape from it. In this sense, it is the reverse of a black hole. Einstein predicted strange cosmic phenomena known as white holes, but scientists have yet to prove they exist.
Today, astronomers race to find the clues that can unlock the secrets of white holes. They investigate the tiny black holes that hide in the most ancient parts of the universe to finally find the smoking gun.

There had been other pirate settlements in different places but none of them had worked quite the same way that Nassau did. There was a fort there. People stayed, they built a community on the land. Larger and larger numbers of pirate-minded people were showing up there and starting to develop an economy around themselves. Men like Edward Thatch, later known as Blackbeard, his sidekick, Black Caesar, a former slave, and the pied pirate that led them all there, Captain Benjamin Hornigold.
In the second episode, tensions rise between Benjamin Hornigold and Henry Jennings; their rivalry takes a new direction when Hornigold declares Nassau a pirate republic.

Magic mushrooms, long considered sacred by the Indigenous Mazatec in Mexico, become the subject of scientific studies measuring the intense effects of its Psilocybin and its potential therapeutic use.
In the second episode, we are introduced to Ben, who’s battled with crippling Obsessive-Compulsive Disorder (OCD) his entire life. When he had his firstborn, Ben’s life became full of panic attacks regarding his son’s safety, and he knew something had to change. Ben signed up for a psilocybin-assisted therapy clinical trial which was testing whether the psychedelic could help people with severe OCD. In the session under the influence of psilocybin, Ben felt decomposed and eventually grew into a tree. While living as a tree, he saw his human self, playing with his child. Though this sounds scary, from Ben’s perspective, it was beautiful. He was one with the universe, seeing himself in the ultimate third-person perspective. Finally, he saw how it could be different if he didn’t let his OCD control him. And several months out, all the symptoms disappeared.
Ben’s story is one of many told in this series, which gives hope that help is right around the corner for the millions who suffer —often in silence— with debilitating mental disorders. But Michael Pollan’s work is showcasing the success stories. Often, even in the most successful trials, psychedelic-assisted therapy only helps up to a third of people enter remission. More frequently, patients are helped —sometimes substantially— but they still suffer with their illnesses and some people aren’t helped at all.