In Bhutan, Palin finds himself back in the land of yaks for a last look at the high Himalaya. Trekking to Chomolhari base camp he meets a nomad with a penchant for yak songs before heading down to Paro to witness the Buddhist festival or Tsechu. In a bar in Thimphu, he discusses reincarnation and the pursuit of happiness with Benji and Khendum, two of the king's cousins, and en route to Bangladesh is taken by Benji to see the rare black-neck cranes. On his journey south through Bangladesh, Michael visits the ship-breaking beaches of Chittagong and grid-locked Dhaka. He meets a man who made a fortune in Birmingham in the poultry business, and a woman who lends money only to women. On a 1920s paddle steamer he is serenaded with the words of Bengal's Shakespeare, and he completes his epic Himalayan journey aboard a fishing boat that carries him out into the Bay of Bengal and a westering sun.

Examines the impact of racism in the 20th century. By 1900 European colonial expansion had reached deep into the heart of Africa. Under the rule of King Leopold II, the Belgian Congo was turned into a vast rubber plantation. Men, women and children who failed to gather their latex quotas would have their limbs dismembered. The country became the scene of one of the century's greatest racial genocides, as an estimated 10 million Africans perished under colonial rule.

This is the story of two tiny animals coming of age. In the wild woods of North America, a young chipmunk is gathering a vital store of nuts ahead of his first winter - in his way are ruthless rivals and giant predators. In the steaming rainforest, a young tree-shrew is forced deep into the jungle to find food. She must draw on all her intelligence and agility if she is to escape the ultimate jungle predator - a reticulated python!

Even after thousands of years of ice crushing the northern hemisphere and temperatures of 20 degrees lower than those of today, many of the great giants of the ice age still walked the earth. It was only when the world had warmed up again that mammoths, woolly rhinos, sabre-toothed cats, giant ground sloths and glyptodonts finally became extinct. Professor Alice Roberts sets off on her last voyage back to the Ice Age to discover why.

The final part reveals how our knowledge of cells has brought us to the brink of one of the most important moments in history. Scientists are close to repeating what has happened only once in four billion years - the creation of a new life form.

D-Day: As It Happens is a 24-hour history event to be broadcast across TV, web, mobile devices and social media, telling the story of this pivotal event in 20th-century history in a completely new way. Using newly-analysed archive footage, viewers can track the progress of seven people who were there on the day, each of them a real participant in the 1944 invasion. And they can do so moment by moment in real time, encountering the twists and turns of the fighting at the same time as the D-Day seven did, and learning their fate as the action unfolds in parallel with the present, Narrated by Peter Snow, with Channel 4 presenter and former marine Arthur Williams, and experts including former British Army officer Colonel Tim Collins and front-line journalist Lorna Ward. The second programme reveals what happened to the seven real people the event is following in real time, and also rounds up the events of D-Day.