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.

The meteoric rise of renewable energy has consequences for our electricity supply. While coal and gas fired power stations can generate electricity whenever you need it, renewables are intermittent by nature. So we need a backup plan for when the wind stops or the sun goes down.
All over the world, engineers and scientists are racing to solve one key problem; how to safely and efficiently store electricity at a huge scale but at a low cost. The quest is producing some truly remarkable ideas and this episode details three of them.

In this mind-bending series, Professor Jim Al-Khalili explores the vast range of size in the universe, from tiny atoms to gigantic, interconnected galaxies.
In the first episode, Jim will enter the world of objects that are too tiny to glimpse with the naked eye. Starting with the smallest insects, he moves on to encounter living cells with amazing superpowers and confronts some of humanity's deadliest enemies in the form of viruses. Going smaller still, he encounters wondrous new nanomaterials such as graphene, discovered by physicist Andre Geim. These are revolutionising engineering, medicine, computing, electronics and environmental science. Finally, Jim comes face to face with the fundamental building blocks of the world around us – atoms – and reveals why understanding the science of the 'small' is crucial to the future of humanity.

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.

In this sixth and final episode, the FBI escalates its pursuit of an elusive hacker, but he soon turns the tables by questioning the legality of a key tool in their investigation.
We'll also find out how one man is being watched by the government for alleged Russian election interference. Is he responsible, or just a patsy for more powerful people? We'll have to get to the end to find out.

In the second episode, panic strikes the community as a full-blown catastrophe looms. Locals mobilize to confront the authorities and protest the nuclear power industry.
Twenty-eight hours after the accident began, the lieutenant governor appeared at a news briefing to say that the plant's owner had assured the state that 'everything is under control'. Later that day, Scranton changed his statement, saying that the situation was 'more complex than the company first led us to believe'. There were conflicting statements about radioactivity releases. Schools were closed and residents were urged to stay indoors. Farmers were told to keep their animals under cover and on stored feed.