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.

Clarkson is ready to submit his application for his farm restaurant; he must use gentle navigation and respect for bureaucracy in order to keep his interests afloat. This, of course, is not easy for Jeremy, so he must be careful. Faced with Council powers that be, Jeremy uses two of his greatest skills: diplomacy and respect for red tape.

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.

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.

Schwalmstadt Maximum Security Prison in Germany. Locked up behind the walls of this 12th-century castle are 188 of Germany's worst offenders. The prison is a fortress surrounded by a moat, and houses dangerous criminals, many of whom attend intense therapy sessions.

As the landscape of work shifts, do we need a drastic rethinking of social safety nets? Do businesses need offices? Is a 9-to-5 workday valid? Does the nation need a drastic rethinking of the social safety nets? Does America face a 'post-work' era, or will there be increased inequities in how we make our livings?