The episode is a journey through the human gut and the process of turning food into energy to keep the body going. Humans have turned eating into culture, a way to celebrate our roots, to bring us together. But food is really just one thing: Fuel. It's where you get the power to live your life. Even when you're sitting completely still, your body needs a lot of energy to stay on. But nowhere is the need for fuel more apparent than when you push yourself to the absolute limit. And the microbiome, the bacteria living in our gut, plays a great role in all this.

Travel writer Simon Reeve embarks upon two long-distance journeys across Turkey, exploring this dramatic and beautiful country that now finds itself at the centre of world events. In this programme, he visits Istanbul and the beaches and crystal clear waters of the Aegean Sea, before ending up at the war-torn border with Syria.
In the region thought to have been the origin of the first vineyards, Simon meets a producer now trying to sell wine in a Muslim country with an increasingly conservative government. In Istanbul, he meets some of the people shaping modern Turkey, from loyal supporters of the nation's controversial and authoritarian president to the master builder constructing one of the world's largest mosques and the notorious billionaire cashing in on a Turkish property boom.
Along Turkey's famous Turquoise Coast, Simon has a taste of luxury at the country's most expensive hotel, but discovers an industry on its knees as war in Syria and deadly terror attacks keep millions of holidaymakers away.

Garry Kasparov is arguably the greatest chess player who has ever lived. In 1997 he played a chess match against IBM's computer Deep Blue. Kasparov lost the match. This film shows the match and the events surrounding it from Kasparov's perspective. It delves into the psychological aspects of the game, paranoia surrounding it and suspicions that have arisen around IBM's true tactics. It consists of interviews with Kasparov, his manager, chess experts, and members of the IBM Deep Blue team, as well as original footage of the match itself.

The cycle of life of a handful of different animals is captured on film in a whole new way in this documentary. Using special motion-control photography equipment, Genesis allows filmgoers to view animal behaviors which are too small, too slow, or too difficult to normally be seen with the naked eye, including a chick hatching its way out from inside an egg, jellyfish drying into nothing under the heat of the sun, or a snake slowly swallowing prey bigger than itself. This footage is accompanied by narration from Sotigui Kouyate, who uses simple props and easily understandable analogies to explain the science behind what its shown on screen. Genesis was directed by Claude Nuridsany and Marie Perennou, who previously created another acclaimed scientific documentary, Microcosmos.

Diarmaid MacCulloch's own life story makes him a symbol of a distinctive feature about Western Christianity - scepticism, a tendency to doubt which has transformed both Western culture and Christianity. In the final programme in the series, he asks where that change came from. He challenges the simplistic notion that faith in Christianity has steadily ebbed away before the relentless advance of science, reason and progress, and shows instead how the tide of faith perversely flows back in. Despite the attacks of Newton, Voltaire, the French Revolutionaries and Darwin, Christianity has shown a remarkable resilience. The greatest damage to Christianity was actually inflicted to its moral credibility by the two great wars of the 20th century and by its entanglement with Fascism and Nazism. And yet it is during crisis that the Church has rediscovered deep and enduring truths about itself, which may even be a clue to its future.

Nathan and Angela accelerate their parenting rehearsal with three-year-old, then six-year-old actors portraying their fake son, 'Adam'. Angela refuses to participate in Halloween due to her belief in Satanic conspiracies.
Nathan balances parenting duties with a rehearsal for Patrick, a man who wants to confront his brother over their late grandfather's will, which bans Patrick from inheriting money if he is dating a 'gold digger'. The rehearsal occurs in a replica Raising Cane's restaurant in a warehouse next to the relocated Alligator Lounge. To introduce real emotions to the rehearsal, Nathan stages a scenario to convince Patrick that he could inherit buried gold from the grandfather of Isaac, the actor who plays Patrick's brother. After Patrick has an emotional breakthrough during a rehearsal, he leaves the production and never returns. Nathan narrates that he is envious that self-deception is easy for some people as he ponders his fake family.