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.'

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.

Across the world, rising demands for food, water and materials have pushed resources to the limit. Many parts of the world have major challenges over fresh water. A lot of soils have a lot of residual pesticides and herbicides. At the same time waste is piling higher. All this demands a new wave of innovation. The challenge is to make more of the things we need without the environmental cost.

Mark has never had a girlfriend, but he wants love more than anything. Maddi and Mark are going on their second date at the Australian Museum. Olivia has had 'a bazillion' unrequited loves but is not ready to give up. Maddi dates a new man who impresses her with his musical talent.

Olivia meets someone who seems to truly get her. Andrew has found out about a speed dating event being held in town. He works on his jokes and James Bond impersonations before going to the dinner. Jimmy and Sharnae go on a special holiday together where Jimmy plans a romantic surprise.

To help Andrew in his search for love, relationship specialist Jodi Rodgers has come to work with him - on his dating skills. Olivia hasn't given up in her search for love. Today, she's on her way to meet someone new. She's meeting Jackson. Jackson likes origami and the smell of perfume. He hates the sound of nails on a blackboard and people slurping their tea. Jimmy and Sharnae are arriving at the Gold Coast for their first-ever holiday together. And Jimmy has a surprise in store for tomorrow.