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.

Even as the science grew more certain, the oil industry continued to block action to tackle climate change in the new millennium. In a revelatory interview, Christine Todd Whitman, George W. Bush's former environment chief, tells the story of how the industry successfully lobbied President Bush to reverse course on his campaign promise to regulate carbon emissions.
Tensions grew between two of the world's biggest oil companies, ExxonMobil and BP, after the latter publicly called for action to tackle climate change. The election of Barack Obama provided hope for supporters of climate action, but the billionaire Koch brothers made an effort to block the new president's attempts to pass climate change legislation, and climate denialism became the mainstream position of the Republican Party. A lawyer who worked for Koch brothers through this period speaks on camera for the first time.

At the top of our planet lies a magical realm, the Arctic Ocean. After four months of winter darkness, the sun returns to reveal a frozen ocean covered in ice. Mother polar bears emerge from their hillside dens and lead their cubs down to the sea ice to hunt, while a young male and female bear forge a surprising friendship out on the ice.
For others, the frozen sea is a trap. A pod of beluga whales has been confined to an ice hole for five months, slowly starving to death as the food around them runs out. Their salvation lies in the strengthening sun that comes with spring, melting the sea ice, allowing their escape.
Off the east coast of Greenland, the floating pack ice in spring is a nursery ground for harp seals. Mothers and pups have just a few weeks together for the pup to learn to swim before she leaves him to fend for himself. But in today’s warming climate, storms can tip helpless youngsters into the sea before they are strong enough to fend for themselves.
Summer is a time of plenty in the Arctic Ocean as plankton blooms feed millions of tiny mouths, such as bizarre skeleton shrimps, as well as the biggest: bowhead whales. These ancient and long-lived whales arrive en masse every year at secret locations known as whale spas. But today, with the loss of summer sea ice, their peace is shattered by orcas from the south. These daring predators are bold enough to take on the much larger bowheads, targeting their vulnerable calves.
The 24-hour daylight of the Arctic summer attracts visitors from afar, including huge flocks of seabirds like crested auklets. A male must use both his song and a secret tangerine perfume if he is to attract a mate. For the resident walrus, the summer heat can be unbearable. After hauling himself to the beach to moult, an old male uses an ingenious technique to get himself back to the cool of the water - a roly-poly!
Summers in the Arctic today bring record-breaking heat. With climate change, it is warming faster than anywhere else on Earth. It is predicted that the Arctic Ocean could become ice-free each summer by 2035, raising new challenges for polar bears. Without sea ice, more and more bears are becoming stranded on remote Arctic islands. It's a dangerous place to be for a mother bear with cubs, surrounded by larger, predatory males.

(Click CC for subtitles) Joseph Sepp Blatter wins a dubious victory as FIFA president. As South Africa is chosen to host the 2010 Cup, rumors swirl around executive Jack Warner.
FIFA is really powerful because it's got the World Cup. And countries fall over themselves to try and host the World Cup in their country. It gives their country image building that you just can't achieve with anything else. The World Cup is the only one event in the world which is broadcasted in the majority of countries. I don't think you can imagine about something else bringing one million people in the street. And the World Cup is the number one way for FIFA to make money. So, because of the power of the biggest football event around the world every four years that gives FIFA and the FIFA president real power and so much leverage over actual countries. But that power is a trap for corruption.

Our frozen planet is changing. In this final episode, we meet the scientists and people dedicating their lives to understanding what these changes mean, not just for the animals and people who live there, but for the world as a whole.
Our journey begins in the Arctic, where every summer huge quantities of ice calve from the edges of Greenland’s melting glaciers. On top of the ice cap itself, glaciologist Alun Hubbard descends into a moulin to try to understand the mechanisms that are driving this historic loss of ice.
Elsewhere in the Arctic, it’s not just land ice that is disappearing. In the Gulf of St Lawrence, Canada, biologists are trying to find out how the loss of sea ice will impact the lives of baby harps. In Arctic Russia, with the loss of summer sea ice, more and more polar bears are arriving on the island of Wrangel. Here, a local ranger and scientists are braving the hungry bears to assess their future survival.
Loss of sea ice impacts not just wildlife but people too. In the remote community of Qaanaaq, Greenland, local Inuit hunters are finding the ice too dangerous to travel and hunt on, risking their traditional way of life. And these changes happening in the Arctic have the potential to affect people far beyond. On Alaska’s open tundra, bubbling lakes hint at the gases being released from the previously frozen soil, including the potent greenhouse gas methane.
There is one place where the full scale of a melting Arctic can be best witnessed - from space. Based in the International Space Station, astronaut Jessica Meir looks down at forest fires across Europe and reflects how our changing weather patterns are interconnected.
Rapid ice loss is also happening across the high mountains of the planet’s continents. Glaciologist Hamish Pritchard uses a sophisticated helicopter-strung radar system to try to quantify how much ice is left in the previously uncharted glaciers of the Himalayas. It’s important as, downstream, some 1.2 billion people rely on glacial meltwater as their primary source of fresh water.
Finally, in Antarctica, we meet Bill Fraser, who has dedicated 45 years of his life to studying the Adelie penguin. Over this period, he has witnessed changes in weather conditions and the extinction of entire colonies. These ‘canaries in the coal mine’ are a sign that all is not well, even in the remotest place on earth. And changes here have the potential to affect all of us, so an international group of scientists is on an urgent mission to assess the stability of a huge body of ice known as the Thwaites ice shelf. If this plug of ice melts and slips into the ocean, it will raise global sea levels, impacting coastal communities across the planet.
The unprecedented changes our scientists are witnessing may be profound, but there is hope that, through a combination of technology and willpower, there is still time to save what remains of our frozen planet.

Experts explore the elusive endeavor of determining the age of the cosmos. Understanding the age of the universe is fundamental to understanding the universe at all. It's at the heart of everything. We want to know how much mass is in it, how much energy is in it, how it behaves. We have to have this number nailed down. The age of the universe enables us to not only understand where we came from, but potentially, the fate of the universe, what will happen millions and billions of years from now.
The idea that the universe grew from a ball smaller than a pinhead is hard to understand, but figuring out when it happened sounds like it should be more straightforward. But it turns out, getting the age of the universe is pretty tricky.