Last in series about the Nazi concentration camp looks at the fate of the remaining prisoners and their guards. Uncovers how many survivors faced appalling treatment in their home countries and how many guards escaped justice.

Last year, just before Thanksgiving, I approached my dad, Leonard Nimoy, about the possibility of working together on a film about Mr. Spock. I had skimmed through some of the books on the making of Star Trek and felt there was so much more to explore about the creation and development of Mr. Spock. And the timing seemed right, as the 50th anniversary of Star Trek the original series was not that far away. Dad agreed that now was the right time, and that he was 100% committed to collaborating with me on this project. He also reminded me that we were (then) just days away from the 50th anniversary of the start of production on 'The Cage,' the original pilot for Star Trek in which dad first appeared as Mr. Spock.

After 400 BC, a new philosophy was born in South east Asia, generated from the ideas of Buddha, a mysterious Prince from India who gained enlightenment while he sat under a large, shapely fig tree. He remains one of the most legendary and influential of all religious progenitors, but what of his actual life? In this biographical documentary, director David Grubin tells the historical tale of Gautama Buddha (563-483 BC), from his initial enlightenment through his death around the age of 80. In the process, Grubin makes an unusual point: that Gautama never once claimed to be God or God's emissary, but instead sought to find a way to bring peace and alleviation from suffering to others in a cruel and often insane world. In telling this story, Grubin combines a number of elements including original animations, testimony by contemporary Buddhists such as the 14th Dalai Lama Tenzin Gyatso, glimpses of sculptures and paintings that help tell Gautama's story, and much more. Narrated by Richard Gere

In the last episode, Iain discovers the remarkable impact of just one plant: grass. On the savannah of South Africa he sees how grass unleashed a firestorm to fight its greatest enemy, the forests. He shows how cutting your finger on a blade of grass shows us how it transformed life in the oceans. In Senegal, he meets the cleverest chimps in the world. And, in the ruins of the oldest temple on Earth, he tells the extraordinary story of how grass triggered human civilisation.

In the second episode, Professor Iain Stewart discovers how flowers have transformed our planet. He journeys to the remote islands of the South Pacific to track down the earliest flowers. In the deserts of Africa and rainforests of Vietnam, he sees how they brought brilliant colour to the most barren landscapes and sculpted the earth itself. And he learns how they drove the evolution of all animals - kick-starting our human story.

Once life arrived in the Galapagos, it exploded into unique and spectacular forms. David Attenborough investigates the driving forces behind such evolutionary innovations. We learn that life must be able to adapt quickly in these ever-changing volcanic landscapes. It has resulted in species found nowhere else in the world, such as giant whale sharks and marine iguanas that can spit sea-salt from their noses, dandelion seeds that grow into tree-sized plants and spiders that can blend perfectly into the darkness. Adaptation has been the key to survival in these islands so far, but the story of life in the Galapagos doesn’t end here. The catalyst that triggers these explosions of life remains in place.