This episode tells the story of how the Emperor Constantine brought Christianity to the western world. In AD 312, Rome was in crisis. The empire had been divided into four parts, each with its own emperor who fought one another. Constantine intervened and united Rome, using military might and a new religion - Christianity.

David Attenborough and the world-renowned scientist Johan Rockström examine Earth's biodiversity collapse. The film explains how humanity has pushed our planet beyond the boundaries that have kept it stable since the dawn of life, but also that this crisis can still be averted, thinking and acting with one unified purpose to ensure that Earth forever remains healthy and resilient.

Could nuclear fusion hold the answers to the energy crisis? It is the process that has forged all matter in the universe. It lights the stars and it is what transformed the lighter atoms that formed in the Big Bang into heavier atoms. In Can We Make a Star on Earth?, Brian Cox peers beyond the glare of our Sun to reveal the hidden forces that provide its power. He discovers how this fusion energy has kept our closest star burning for five billion years. Brian believes humanity must build a star on Earth to ensure survival. Will scientists be able to harness fusion power and achieve abundant, cheap, clean energy?

Michael Moore returns to controversial territory with this documentary examining the events that led to the last global financial crisis, while putting forward an indictment of the current economic order in the United States and unfettered capitalism in general. Topics covered include Wall Street's "casino mentality", for-profit prisons, Goldman Sachs' influence in Washington, D.C., the poverty-level wages of many workers, the large wave of home foreclosures, corporate-owned life insurance, and the consequences of "runaway greed".

In February 2009, Michael Moore issued an appeal to people who worked for Wall Street or in the financial industry to share first hand information, requesting, 'Be a hero and help me expose the biggest swindle in American history'. He uncovers the social costs of corporate interests pursuing profits at the expense of the public good.

The last episode explores Mescaline, the psychoactive molecule in San Pedro and peyote cacti, a sacred medicine that Native Americans have had to fight for the right to use. At the Indigenous practices there's always an elder, someone who knows the territory very well, who's presiding. There's usually a group, a community is involved, There's always an intention, a purpose to what you're doing, and you're treating it as sacred, in order to achieve altered states of consciousness, which contribute to worship in various ways, or celebration or healing.
But maybe all this is not so new to Western culture after all. In the old Greek histories of Eleusis, people who were initiated there got the drink, the kykeon, and then they had the illumination. The precise recipe is a mystery, but we know that the kykeon was a psychoactive brew that was used at the Eleusinian mysteries, a sacred annual ritual of enlightenment practiced by some of the world's greatest minds including Socrates, Plato, and Aristotle. So why did this ritual come to an end more than 1,000 years ago? Was the possibility of illumination or achieving a higher consciousness considered threatening to the powers that be? Have the drug wars been merely an extension of that fear?
Psychedelics has a major part in how we can heal as a community, how we can heal as a city, and how we can heal as a country. The current renaissance of psychedelics could not come at a better time as the world confronts a crisis in mental health. But psychedelics have much to offer. The psychedelic experience changes the mind in ways that will help scientists better understand how it works. All these altered states allow us to probe what is the greatest mystery in all of nature. The emergence from mere matter of something as miraculous as consciousness. But an even bigger question is whether psychedelics might help us address the environmental crisis of how we think about our place in nature. One of the greatest gifts of psychedelics is how they reanimate the natural world, allowing us to perceive the subject, the spirit of all species, not just our own. And to feel a deeper sense of interconnectedness with nature.