The third episode looks at anxiety and explores why it is so common. It talks to neuroscientists who explain the physiological and evolutionary basis of anxiety. Although it can help animals escape predators, anxiety can cause serious problems for human beings. It talks to sufferers of anxiety and examines the different types of anxiety people can feel. It also looks at how social media can cause anxiety.

Mixing comedy with a thorough investigation of psychedelics, the film explores the pros, cons, science, history, future, pop cultural impact, and cosmic possibilities of hallucinogens. The documentary features comedic tripping stories from A-list actors, comedians, and musicians. Star-studded reenactments and trippy animations bring their surreal hallucinations to life.
'Have a Good Trip' tackles the big questions: Can psychedelics have a powerful role in treating depression, addiction, and helping us confront our own mortality? Are we all made of the same stuff? Is love really all we need? Can trees talk?

Dr Chris van Tulleken, Dr Hannah Fry and Michael Mosley examine the latest research and explore some of the big questions about Covid-19 and the pandemic it has created. Michael visits the UK government's high-security laboratory Porton Down, where vaccines are being tested. He also uncovers what the experience of the 2002 SARs epidemic reveals about this one. Both were caused by coronaviruses, but certain key changes to today's virus have allowed it to infect the world, where SARs was contained.

When Homo sapiens, which means 'wise ones,' discovered and controlled fire hundreds of thousands of years ago, everything changed. Fire allowed us to cook food and heat dwellings, and it served as a focal point for storytelling and sharing cultural identity among community members. We don't yet have established parameters for what it means to be 'distinctly human,' It would seem the only thing that separates us from other animals, Neil deGrasse Tyson ponders, is our neurotic need to feel 'special'. Against the backdrop of the Halls of Extinction, Tyson insists that there must be a clear distinction between ourselves and animals that justifies our eating them, wearing them and even bringing an end to their species.
From the birth of the devil in ancient Persia to a searing story of saintliness among macaque monkeys, this episode is an exploration of human potential for change. It concludes with the story of how one of history's greatest monsters was transformed into one of its shining lights.

The fourth episode sees host Neil deGrasse Tyson exploring our eternal quest to end hunger and honoring Nikolai Ivanovic Vavilov, pioneer of modern plant breeding, who risked his life for a discovery that would change the history of science. Vavilov's story is marked by both the tenacity and creativity and is particularly tragic. Interwoven into Vavilov's somber narrative are warnings and treatments of science and its ethical implications, especially when science itself comes under attack from political forces.

In just over 100 days, a new coronavirus has taken an unprepared world by storm, infiltrating every corner of the globe, sending entire nations into lockdown, killing thousands and infecting countless more. Across the world, governments are scrambling to react, hospitals are struggling to cope and an increasingly anxious public are starting to panic.
The world's media is awash with data, information and misinformation. But what are the facts? What is COVID-19 and why is this strain of coronavirus so dangerous? What happens in our bodies when the virus attacks? How does this compare to previous pandemics? What do all the the numbers really mean, and how can data modelling help us look for an exit strategy? This programme investigates the scientific facts and figures behind the biggest public health crisis in living memory, and explores the latest research from the frontline of the medical and scientific fightback.