As the journey continues, there's beauty and danger in equal measure. Charley and Ewan travel through the extraordinary Bolivian desert, but the sandy roads make all more difficult. The duo ride their electric bikes through the exotic and breathtaking countryside and all the way making a challenging ascent. The riders stay in a hotel made entirely out of salt before heading to La Paz. 'Bolivia' also shows some quality work done by UNICEF when it comes to educating and working with the children. McGregor and Boorman spend time with the kids before resuming their journey and ending with a ferry ride over lake Titicaca.

Planets beyond our solar system are known to astronomers as exoplanets. They are at trillions of miles from Earth and yet, it might be possible to detect a faint signature of life in them. From the light of the stars they orbit that passes through the atmosphere of an exoplanet, it is possible to capture the chemical fingerprint of the elements in that atmosphere.
The fictional world Eden is orbiting not one star, but two. The light from its twin stars powers photosynthesis, pumping more oxygen into the atmosphere than in Earth, allowing life to thrive. Grazers are constantly alert to danger, because the canopy is home to predators perfectly evolved to live among the trees. In Episode 3, another topic are fungi and the role they could play on exoplanets. Ecologist Thomas Crowther talks about the role mycelial networks play in the Rothiemurchus forest in Scotland.

Each night, across the planet, our cities illuminate the darkness. Their lights burning brighter than ever before. And whilst we're asleep, animals are making the most of this new neon landscape. The sunset in Los Angeles, Chicago, and Toronto creates worlds of opportunities for the cleverest animals willing to take the risk.

Global CO2 emissions coming from aviation will go from about 2% to, by 2050, something closer to 20%. Technology is the only key to open up a brighter future that can be sustainable at the same time. The way we fly is about to change, driven by a new breed of aviators not afraid to think differently. From clean, green electric aircraft to autonomous sky taxis, could the days of the jet age be numbered?

Grasslands cover one quarter of all land and support the vast gatherings of wildlife, but to survive here animals must endure the most hostile seasonal changes on the planet. From Asia's bizarre-looking Saiga antelope to the giant anteaters of Brazil, grassland animals have adapted in extraordinary ways to cope with these extremes. In the flooded Okavango, lions take on formidable buffalo in epic battles, on the savannah bee-eaters take advantage of elephants to help catch insects and, on the freezing northern tundra, caribou embark on great migrations shadowed by hungry Arctic wolves.

Nintendo was like an impossibly huge wall. But if Mario was the undisputed king, an underdog was about to declare war. For Japanese game maker Sega, mainly known for its arcade cabinets, the battle was about winning the home console market. Sega's Genesis console and its speedy character, Sonic, hit the market.
In the early '80s, sports video games existed, but they didn't really look real. And one visionary entrepreneur had already started tackling the challenge of taking sports from the stadium onto the screen. Electronic Arts kicks off a partnership with football legend John Madden.