The fourth episode starts off with the two riding through Santa Cruz, Argentina. The plan is to cross over into Chile and then going up into the Andes. Ewan and Charley head through Argentina’s red rock landscape while a member of their team copes with altitude sickness. The duo are well and truly underway and the first signs of all are well is how well the Harleys hold up in challenging conditions. The roads alternate between unforgiving and pleasant and these e-bikes push through effortlessly. As they ride through Chilean Andes, the audience is shown a picturesque view of the beauty of the countryside, an experience which Boorman calls 'magical.'

Even 2,000 years after his death, General Hannibal's battle strategies are still studied today. But of all his military feats, perhaps his greatest was leading his massive Carthaginian army of men and three-dozen elephants across the Alps and into the heartland of Rome in 218 B.C. Until now, the route they took has been a matter of dispute, but thanks to modern-day technology, geomorphologist Bill Mahaney and microbiologist Chris Allen believe they've accurately traced this ancient journey.

As the journey continues, there's beauty and danger in equal measure for Charley Boorman and Ewan McGrego. The duo ride their electric Harleys through the exotic and breathtaking Bolivian countryside in a tough ascent. The sixth episode showcases some of the challenges the hosts and the crew face when they scale the terrain. One of the Rivians runs into trouble while sandy roads and a heavy breeze sees Boorman take a tumble. Apart from all the accidents, the chapter also shows some quality work done by UNICEF when it comes to educating and working with the children in Bolivia.
The altitude sickness hits Taylor, their logistics man real bad and McGregor starts feeling it as well. The episode ends with a doctor heading to his hotel room to check up on him.

One man has seen more of the natural world than any other. This unique feature documentary is his witness statement. In his 93 years, David Attenborough has visited every continent on the globe, exploring the wild places of our planet and documenting the living world in all its variety and wonder. Now, for the first time he reflects upon both the defining moments of his lifetime as a naturalist and the devastating changes he has seen. Honest, revealing and urgent, this film is a powerful first-hand account of humanity's impact on nature and a message of hope for future generations.

Set in the dark underbelly of Silicon Valley, The Social Dilemma fuses investigative documentary with enlightening narrative drama. Expert testimony from tech whistle-blowers exposes our disturbing predicament: the services Big Tech provides-search engines, networks, instant information, etc.-are merely the candy that lures us to bite. Once we're hooked and coming back for more, the real commodity they sell is their prowess to influence and manipulate us.

Across the universe, galaxies are going dark, and scientists don't know why the stars are losing their shine. Something is slowly drawing the curtains closed on the universe. Our milky way is under threat. Astronomers race against time to uncover the truth behind how galaxies are born and how they die before all of the lights go out.