Fifty years ago there were close to half-a-million lions in Africa. Today there are around 20,000. To make matters worse, lions, unlike elephants, which are far more numerous, have virtually no protection under government mandate or through international accords. This is the jumping-off point for a disturbing, well-researched and beautifully made cri de coeur from husband and wife team Dereck and Beverly Joubert, award-winning filmmakers from Botswana who have been Explorers-in-Residence at National Geographic for more than four years. Pointing to poaching as a primary threat while noting the lion's pride of place on the list for eco-tourists-an industry that brings in 200 billion dollars per year worldwide-the Jouberts build a solid case for both the moral duty we have to protect lions (as well as other threatened "big cats," tigers among them) and the economic sense such protection would make. And when one takes into account the fact that big cats are at the very top of the food chain-and that their elimination would wreak havoc on all species below them, causing a complete ecosystem collapse-the need takes on a supreme urgency.

Follow the life and career of Portuguese footballer Cristiano Ronaldo, who currently plays for Spanish club Real Madrid and the Portugal national team, through a series of interviews with Ronaldo himself as well as friends and family. Directed by Anthony Wonke and executive-produced by Asif Kapadia, Ronaldo was shot over the course of 14 months with the film-makers gaining access to Ronaldo's private life and inner circle of friends, family and team-mates. The film was shot in Madeira, Lisbon, and Madrid, where he currently resides as a squad member of Real Madrid.

In this episode, Helen seeks out the colours that turned planet Earth multicoloured. To investigate the essence of sunlight Helen travels to California to visit the largest solar telescope in the world. She discovers how the most vivid blue is formed from sulfur atoms deep within the Earth's crust and why the presence of red ochre is a key sign of life. In gold, she discovers why this most precious of metals shouldn't even exist on the surface of the planet and in white, Helen travels to one of the hottest places on Earth to explore the role salt and water played in shaping planet Earth.

An exploration of Earth's cosmic neighbourhood. Looking beyond the borders of our solar system, what's nearby in our galaxy? How do the other objects in our local area influence life on Earth? And, how did Earth's place in the galaxy make it the perfect place for the development of advanced life? Now that the Voyagers have visited the outer planets of the solar system they are heading for new adventures in places astronomers call the Oort Cloud, the heliopause, heliosheath and eventually they may encounter double stars and exoplanets, some of which may pay a visit to the solar system one day or explode showering us with radiation. If the Voyagers live so long they will experience the local fluff, local bubble and other parts of the habitable zone of the galaxy.

David Attenborough discovers the plants that have evolved to shed their dependency on water enabling them to survive in the driest environments. The story begins at midnight in midsummer as David steps into the Princess of Wales Conservatory to witness the extraordinary nocturnal blooming of a cactus. The queen of the night, with its giant flowers, is the centre piece of a stunning symphony of cacti blooms that burst open in the desert (and at Kew) at night. In a mesmerizing 3D slow motion sequence, we discover the extraordinary connections between cacti and their natural pollinators: bats. As the sun rises, David meets other amazing plants. Species like the century plant, the Agave franzosini, which grows steadily for over 50 years, only to then flower itself to death with one mighty telegraph pole sized bloom which literally bursts out of the roof of Kew’s green house.

This episode tells the tale of what's broadly considered China's most creative dynasty - the Song (960-1279). Michael Wood heads to the city of Kaifeng, the greatest city in the world before the 19th century. Here in Twin Dragon Alley, locals tell him the legend of the baby boys who became emperors.
He explores the ideas and inventions that made the Song one of greatest eras in world culture, helped by China's most famous work of art, the Kaifeng scroll, which shows the life of the city in around 1120. A chef makes Michael a recipe from a Song cookbook, while a guide to 'how to live happy, healthy lives for old people', published in 1085 and still in print, is discussed with local women doing their morning exercises. The Song was also a great era for scientific advance in China. Michael steers a huge working replica of an astronomical clock, made by China's Leonardo da Vinci.
Then at a crunch Chinese Premier League match, Michael tells us the Chinese invented football! The golden age of the northern Song ended in 1127, when invaders sacked Kaifeng, but they survived in the south. At their new capital, Hangzhou, Wood joins locals dancing by the West Lake, while in the countryside he meets Mr Xie with his records of 40 generations of ancestors. The final defeat of the Song took place in a naval battle in the estuary of the Pearl River in 1279. When all was lost, rather than surrender to the Mongols, a loyal minister jumped into the sea with the young boy emperor in his arms. 'So ended the glory of the Song', Wood concludes, 'but a new age would arise... as in China, it always has!'.