For the past century, Russian history has also been the history of its security services. They were used by the Soviet state to crush dissent. Millions suffered at their hands. Mass executions, secret wars, spies capable of stealing the atomic bomb, poisoning scandals all add up to the most extraordinary and dangerous security network the world has ever known. But even today, the security network is arguably stronger than ever. This is the History of the KGB, told through its veterans and its victims.
Founded in 1917, Cheka was the predecessor organization of the KGB. Set up as a 'temporary' measure by Lenin, unknown number of Soviet citizens would die at the hands of the secret services as internal dissents in the 1920s. An inglorious chapter is the "Great Terror" phase, when millions of Soviet citizens were convicted and executed in mock trials under Stalin's rule in the 1930s. Outside the Soviet Union, during the WWII they were busy infiltrating German High Command, British Intelligence and America's Manhattan Project. The Cold War had begun in earnest.

Mid-1942, as Hitler’s forces are pushing into southern Russia to take the oilfields, he spies a city prized by his enemy Stalin – Stalingrad. If Hitler can capture this city, he can expand his empire all the way to the Urals. But what Hitler hasn’t counted on is the enormous resilience of the Soviet people; men and women willing to defend their Motherland at all costs.
What ensues at Stalingrad is one of the bloodiest battles in the history of warfare, with an estimated 2 million total casualties, and an event that turns the tide for the Germans.

Located in Central America, Tikal is one of the largest of the ancient cities of the Mayan civilization. Occupied for more than a millennium, Tikal, founded in the 8th century BC and nestled in the jungle of Guatemala, will have up to 12,000 structures and reach over 2 million inhabitants.
This episode shows its extraordinary pyramid-temples, designed with human power alone. Thanks to new technologies, the ancient Mayan city is revealed there, entirely reconstituted in 3D synthetic images.

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.

We may be smart, but we're still discovering animals have countless skills, every bit as impressive. In a world full of unexpected foes, competition is evolution's ultimate driving force. Is the secret behind the incredible diversity of life on earth, and the most extraordinary animal powers.