As almost all animal inhabitants of Antarctica are forced to migrate north, the sea underneath the frozen ice still provides a home to many specially adapted fish whose cells are protected from freezing through an 'antifreeze' liquid. Many of them feed on the faeces of other animals. The most notable larger animal that does not migrate north is perhaps the Weddell Seal, which can be found as close as 1300 kilometres to the pole. Groups of seals tear holes into the ice to dive for food and come up to breathe. The females come back to the ice to give birth. This episode also describes primitive plant life such as lichen, which can still be found on the continent in winter, even in the extremely dry and permanently frozen valleys conditions under which dead animals can lie frozen for many centuries without decomposing. It details the life of the Emperor Penguin, 'the only birds to lay their eggs directly on ice'. While other animals retreat, Emperors migrate not just to the ice, but into the Antarctic continent. The females lay eggs which are incubated by the males under the harshest conditions on Earth (huddling closely together for warmth), while the females return to the sea.

Dr Adam Rutherford takes the viewer on a rollercoaster ride as he explores the consequences of one of the biggest scientific projects of all time - the decoding of the entire human genome in 2000. In The Book of Life Adam discovers that every human carries the entire story of life on earth hidden in his or her DNA and sees how we are all linked directly to the origins of life and to the first creatures with backbones. He also investigates the implications of the fact that for much of its existence, the human race was an endangered species.

Jessie Buckley narrates the extraordinary story of the first transatlantic communications cable. In 16 August 1858, a short message is telegraphed from County Kerry to Newfoundland, 3,000km away: ‘Europe and America are united by telegraph. Glory to God in the highest, on earth peace, good will towards men.’ The Morse code message is conducted along the new underwater transatlantic telegraph cable laid across the bed of the Atlantic Ocean. Sending the same message by ship would have taken at least ten days, but the transmission takes just hours and heralds the dawn of the modern communications age.
The quest is driven by visionaries and pioneers. Among them are Cyrus Field, a wealthy businessman who, despite his immense success, ends his life in poverty; Samuel Morse, inventor of the telegraph and Morse code; Isambard Kingdom Brunel, the British engineer who pushes boundaries and budgets; and Belfast physicist Lord Kelvin, who calculates how to achieve what had hitherto been deemed impossible. Together, their ingenuity and relentless pursuit helps realise one of the great scientific accomplishments of their age for which Valentia, on Ireland’s remote western coast, is ground zero.

The documentary tells the story of the extremely rare discovery of evidence of Roman crucifixion, unearthed in a routine archaeological dig in the Cambridgeshire Fens. When human remains were found alongside a variety of Roman artifacts, none of the team at Albion Archaeology saw anything out of the ordinary. But once the bones were washed back at HQ, something highly unusual was uncovered: a nail through the heel bone of one of the individuals. Could this be evidence of a Roman crucifixion? When they did some research, they found that only one confirmed example had ever been unearthed before, discovered in the 1960s in Jerusalem. To find out more, they called in renowned osteoarchaeologist Dr Corinne Duhig to investigate. With exclusive access to Corinne’s investigation and the remains themselves, The Cambridgeshire Crucifixion sets out to find out who this person was, how they lived and why they were put to death in this notoriously gruesome way. We perform a CT scan, DNA and isotope analysis of the remains, and use them to create a cutting-edge virtual autopsy of the skeleton, conducted by Corinne and one of her former students, biologist Prof Ben Garrod.
A supporting cast of expert contributors help to analyse the artefacts found at the Fenstanton site and reveal a compelling picture of life in Roman Britain in the 1st century CE. The film culminates in a world first: a full forensic facial reconstruction of a victim of Roman crucifixion, conducted by world-leading expert Joe Mullins.

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.

This episode is centered around how science, in particular the work of Clair Patterson (voiced in animated sequences by Richard Gere[33]) in the middle of the 20th century, has been able to determine the age of the Earth. Tyson first describes how the Earth was formed from the coalescence of matter some millions of years after the formation of the Sun, and while scientists can examine the formations in rock stratum to date some geological events, these can only trace back millions of years. Instead, scientists have used the debris from meteor impacts, such as the Meteor Crater in Arizona, knowing that the material from such meteors coming from the asteroid belt would have been made at the same time as the Earth. Patterson also examined the levels of lead in the common environment and in deeper parts of the oceans and Antarctic ice, showing that lead had only been brought to the surface in recent times. He would discover that the higher levels of lead were from the use of tetraethyllead in leaded gasoline resulting in government-mandated restrictions on the use of lead.