It is Christmas Day in the house of Hastings. The time (the 1830s), the place (a suburban Victorian home), and the atmosphere (after the pudding with the children waiting to be entertained) are ripe for father to stun his audience with his knowledge of the world of natural philosophy. It is a world of exploding biscuit tins, unpredictable hard-boiled eggs, singing drainpipes, and enough amateur science to make young enthusiasts reach for their bunsen burners, and mothers for their smelling salts.

In this special episode, Horizon reports on Erich von Däniken and his theories about astronauts visiting Earth long ago.

This special episode of Horizon shows the latest advances in research into how the visual eyesight system of humans and animals work.

This Horizon special episode recalls the highlights of the past 25 years of the space age.

In the first part of this special two-part series, Horizon reports on the yellow rain problem in South-east Asia.

In this special episode, Horizon brings you a report on space exploration and exploitation. The first half of this episode looks back at the Apollo 11 moon landing, and second the second half looks at the future plans of the space program.

This is the second part, of a two-part special series. In this episode, Horizon looks at the history of germ warfare and the research still continuing today in military labs under deceptive name of defensive biology.

Horizon celebrates twenty one years of work, achievement, and awards with a birthday compilation of highlights from past episodes.

This report by Horizon looks into how the apparitions of Halley's comet came to be predicted so accurately.

Special on Halley's comet

This Horizon special follows the 20 months preparation of the five astronauts who are to man the American space shuttle Discovery launching on the 29th of September in 1988. This is the first shuttle flight since the Challenger disaster in January 1986.

This Horizon special explores the production and processes behind the scenes of the new five pound note to be launched on the 7the June, 1990, in Britain. It considers the design and production of money and the intricate techniques developed to prevent forgeries.

This Horizon special episode is part one of a three part series on the projects, cosmonauts, and engineers involved in the Soviet Union space program.

This Horizon special episode is part two of a three part series on the projects, cosmonauts, and engineers involved in the Soviet Union space program.

This Horizon special episode is the last part of a three part series on the projects, cosmonauts, and engineers involved in the Soviet Union space program. In this episode, two Soviet cosmonauts risk their lives earlier this year in a dangerous space walk to try and repair their stricken craft.

This Horizon special program explores what happened when the "Giotto" explorer spacecraft passed within 100 kilometres of Halley's Comet.

This documentary by Horizon reveals the disturbing discoveries made in over 40 inspections looking for weapons of mass destruction in Iraq.

This report by Horizon brings you the results of a landmark survey about sex.

This Horizon special looks at the mysterious changes in wildlife that has been reported in the USA and that man's reproduction may also be adversely effected.

Horizon celebrates its 30th birthday by checking on some of the scientific predictions of last three decades.

In this special episode, Horizon examines the use of foetal surgery for life saving operations.

First part of a two-part drama looking at the work and life of Albert Einstein. Mixes archival material with dramatised sequences. Looks at his turbulent private life and the six month period in which he worked out the size of atoms, the quantum theory of light and invented the Special Theory of Relativity.

This is the second part of a two-part Horizon series on Albert Einstein looking at Einstein's life and work. This program deals with the break up of his first marriage, his second marriage to his cousin, and the completion of the General Theory of Relativity which replaced Newton's view on gravity.

First part of a two-part investigation into BSE. Looks into the scientific confusion and official bungling surrounding the problem, which allowed BSE to spread into the human population. Includes an interview with Sir Richard Southwood, Chairman of the first Government advisory committee, who reconsiders evidence they first weighed up in 1988.

This is part two of a two-part Horizon series on Bovine Spongiform Encephalopathy (BSE), more commonly known as "mad cow" disease, and how it is transmitted to humans, becoming CJD (Creutzfeldt Jakob disease), how many people are at risk, and what the chances are of finding a cure.

An update on the earlier 1992 episode, and the continuing story of the Carbon 60 molecule.

Follows archeologist Natalya Polosmok as she journeys to the Altay Mountains in southern Siberia to search for traces of an ancient people known as the Pazyryk. * Polosmok and her team discover and unearth a wooden tomb surrounded by the frozen remains of six horses, uncovering a 2,400-year-old woman dubbed the Siberian Ice Maiden. * The Ice Maiden is buried alone, lying as if asleep, in a wood coffin with a headdress and a mirror. An afterlife meal, a yak horn vessel and a wooden table are also found outside the coffin. Archeologists record the Ice Maiden's height, and discover a hole in her skull and peat packed in her body. *They use radiocarbon dating, tree-ring chronology and biological testing to determine the age of the remains and time of death. *The body is excavated and taken to Moscow for preservation and facial reconstruction. Another mummy, and other skeletons, are discovered elsewhere. *The program concludes by raising the question of who has rights to the ancient graves.

In this second part of the Ice Mummies trilogy, attention turns to Ötzi, the Neolithic man plucked with an ice pick and some not inconsiderable brute force from an Alpine glacier. Once again, as with the Ice Maiden, an impressive set of relationships are on display in the vicinity of the leathery character and his bedraggled belongings. By far the most important man in Ötzi's life is Konrad Spindler, whose chance identification of the age of the mummy upon its discovery catapulted him to stardom and a life of analysis and scientific monitoring. Spindler is fiercely defensive of Ötzi, like Frankenstein and his monster, although the relationship is much less emotional than Natalia and her Ice Maiden. A bewildering array of more minor characters emerge during the course of the film, my particular favourite being a yodeling mountain dweller, included as a representation of how Ötzi has effected the local population. All varieties of archaeological life appear in this film, from Professors zur Nedden and Seidler, whose double act hints at the Muppets Stadtler and Waldorf, to an extra from This is Spinal Tap, Hanspeter Schrattenthaler, whose bare chest and rock star poses suggest he dearly wishes his copper axe were a guitar. Also worthy of mention is the lovable Harm Paulsen, who lives and works in a reconstruction of a Neolithic village and whose lilting Danish tones express some of the more human elements of the sad demise of Ötzi, such as the family he may have left behind, providing a stark contrast to the strictly 'scientific' views of Spindler.

This is the bizarre and fascinating story of the remains of Inca culture, frozen for posterity high in the mountains of the Andes. Evidence has emerged of sacrifice to the mountain gods, whose existence dominated the civilization over 500 years ago. The film traces the frozen bodies of children uncovered by archaeologists in South America, and follows an archaeological expedition to a high-altitude sacred site in search of ritual remains and another body. How did they come to be there? Why did they go to their deaths willingly? What was the religious framework that dictated their sacrifice to fierce gods?

This is part one of a three-part Horizon special about the scientists and others who became explorers in the earth's final frontier, Antarctica.

This is part two of a three-part Horizon special about the scientists and others who became explorers in the earth's final frontier, Antarctica.

This is part three of a three-part Horizon special about the scientists and others who became explorers in the earth's final frontier, Antarctica.

This programme traces the lessons learned from a century of road fatalities. How have car makers learnt to predict the injuries their designs will inflict, and how have doctors learnt to patch up the damage to the frail human body?

In this documentary special, Horizon explores how to solve the problem of sailors being unable to pin-point their exact east-west position on the globe.

Horizon presents a three-part series focusing on weight-gain, dieting, and eating disorders. In this episode, there is scientific proof that we are not always in control of our appetites and weight, and introduces the hormone called Leptin.

Horizon presents a three-part series focusing on weight-gain, dieting, and eating disorders. In this episode, Horizon examines the shift away from invasive dieting methods to more natural weight-loss strategies, based on products already present in the food we eat.

Horizon presents a three-part series focusing on weight-gain, dieting, and eating disorders. In this episode, Horizon looks at the eating disorders called Anorexia and Bulimia.

This is part one of a two-part special Horizon series about Atlantis. In this episode, Horizon explores the mystery of whether Atlantis really did exist. Was there really, about 12,000 years ago, a fabulous city whose people had already evolved into a sophisticated civilization with culture and society, writing, astronomy, religion, monument-building, while everyone else was still living in the Stone Age?

This is part two of a two-part special Horizon series about Atlantis. In this episode, Horizon puts Graham Hancock's controversial theories about the past to the test, dissecting his evidence for a lost civilization.

Will we find the magic formula that allows us to live forever in the 21st Century?

Ancient diseases we thought we had defeated are returning to haunt us, and plagues of new viruses and bacteria are now emerging.

Will we ever be able to hand-pick genes to manufacture our own tailor-made baby?

Horizon explores how the search for Martians is hotting up.

Tantalising new evidence has emerged that life could exist on Mars. But to find out for sure humans will have to journey to this dry, frozen planet.

In August 2000, the Russian submarine, the Kursk, sank with the loss of 118 lives. It was a tragedy which shocked the world. But to many the tragedy remains incomprehensible, for the Kursk had been built to be unsinkable. How could this submarine have foundered?

In this documentary, Horizon reports on a skeleton was found 50 years ago in Southern Italy. The bone structure suggests the owner was an ancient athlete.

A team of doctors conducts potentially life-saving experiments in Horizon's 'death zone' This two-part special follows a team of doctors conducting a series of groundbreaking experiments as they climb Everest, the world's highest peak. From their laboratory tents, pitched in -25&degC conditions, the experts use their own bodies for medical tests. They push themselves to the limit to better understand the human body's behaviour in a low-oxygen environment. The team hopes their work will lead to new, life-saving treatments for intensive care patients suffering from hypoxia, a shortage of oxygen in the body.

A team of doctors conducts potentially life-saving experiments in Horizon's 'death zone' This two-part special follows a team of doctors conducting a series of groundbreaking experiments as they climb Everest, the world's highest peak. From their laboratory tents, pitched in -25&degC conditions, the experts use their own bodies for medical tests. They push themselves to the limit to better understand the human body's behaviour in a low-oxygen environment. The team hopes their work will lead to new, life-saving treatments for intensive care patients suffering from hypoxia, a shortage of oxygen in the body.

Professor Jim Al Khalili delves into over 50 years of the BBC science archive to tell the story behind the emergence of one of the greatest theories of modern science, the Big Bang. The remarkable idea that our universe simply began from nothing has not always been accepted with the conviction it is today and, from fiercely disputed leftfield beginnings, took the best part of the 20th century to emerge as the triumphant explanation of how the universe began. Using curious horn-shaped antennas, U-2 spy planes, satellites and particle accelerators, scientists have slowly pieced together the cosmological jigsaw, and this documentary charts the overwhelming evidence for a universe created by a Big Bang.

First of a two-part special. Ten volunteers have come together for an extraordinary test. Five are 'normal' and the other five have been officially diagnosed as mentally ill. Horizon asks if you can tell who is who, and considers where the line between sanity and madness lies.

Second part of the special documentary considering where the line between sanity and madness lies as ten volunteers come together for an extraordinary test. With five 'normal' volunteers and five who have been officially diagnosed as mentally ill, Horizon asks if you can tell who is who.

Professor Brian Cox takes a look through nearly 50 years of BBC archive at the story of man's relationship with the Moon.

In the wake of the swine flu outbreak, virologist Dr Mike Leahy goesw back over 50 years of BBC archives to explore the history of pandemics: waves of infectious diseases caused by bacteria, viruses or parasites. Inspired primarily by the Horizon back catalogue, he works his way through the diseases that have been tackled head-on through the 20th Century: polio, malaria, smallpox, AIDS, and up to the present day with SARS and the H5N1 bird-flu virus. Each pandemic episode tells us something about the world and our place within it. In his trip through the ages and the archives, Dr Leahy charts science's ongoing battle with nature and questions which one is winning. He makes a reasonable fist of the exercise, but is somewhat up against it as his source material can be patchy - first triumphant about man's successes and then defeatist when the previous triumph didn't work out quite as planned, etc.

The intriguing possibility of life on Mars has fuelled man's quest to visit the Red Planet. Drawing on 45 years of Horizon archive, space expert Dr Kevin Fong presents a documentary on Earth's near neighbour. Man's extraordinary attempts to reach Mars have pushed technological boundaries past their limit and raised the tantalising prospect of establishing human colonies beyond our own planet. While the moon lies 240,000 miles away, Mars is at a distance of 50 million miles. Reaching the moon takes three days, but to land on Mars would take nearly eight months, and only two thirds of the missions to Mars have made it. The BBC has been there to analyse the highs and lows - including the ill-fated British attempt, the Beagle. Horizon has explored how scientists believe the only way to truly understand Mars is to send people there. If and when we do, it will be the most challenging trip humanity has ever undertaken.

In a Horizon special, naturalist Sir David Attenborough investigates whether the world is heading for a population crisis. In his lengthy career, Sir David has watched the human population more than double from 2.5 billion in 1950 to nearly seven billion. He reflects on the profound effects of this rapid growth, both on humans and the environment. While much of the projected growth in human population is likely to come from the developing world, it is the lifestyle enjoyed by many in the West that has the most impact on the planet. Some experts claim that in the UK consumers use as much as two and a half times their fair share of Earth's resources. Sir David examines whether it is the duty of individuals to commit not only to smaller families, but to change the way they live for the sake of humanity and planet Earth.

Dr Susan Jebb takes a look through nearly fifty years of amazing BBC archive of mankind's relationship with what we eat, charting the shift from the malnutrition of the past to today's obesity epidemic. This is the story of our attempt to control nature through the wholesale industrialisation of food production in our search for enough to eat, and the consequences of that massive shift in our diet on the shape of our bodies, and the diseases that kill us. From the BBC's original eccentric scientist Magnus Pyke comparing the virtues of artificial additives to a Beethoven sonata, to the tragic side effects of diet pills, Horizon and the BBC have covered it all. On her journey through the decades, Dr Jebb explores how scientists have played a crucial role both in transforming the way our food is produced, but also in attempting to understand the biological mechanisms that determine why it is that some of us have become so large.

As the Pope ends his visit to Britain, historian Dr Thomas Dixon delves into the BBC's archive to explore the troubled relationship between religion and science. From the creationists of America to the physicists of the Large Hadron Collider, he traces the expansion of scientific knowledge and asks whether there is still room for God in the modern world.

Dallas Campbell delves into the Horizon archive to discover how our understanding of intelligence has transformed over the last century. From early caveman thinkers to computers doing the thinking for us, he discovers the best ways of testing how clever we are - and enhancing it.

Professor Iain Stewart examines the powerful geological forces that unleashed the devastating Japanese earthquake, and explores how the release of this power of the planet brought Japan to the brink of a nuclear meltdown. He follows moment by moment how the earthquake was generated under the Pacific Ocean, travelled to the Japanese mainland, and the rare conditions that unleashed a tsunami. He also reveals the latest science behind earthquakes - from why we can't predict them, to what causes some of them to reach such power. Iain shows why our civilisation has developed such a dangerous relationship with earthquakes, and why millions of us continue to live in earthquake zones across the world.

In 2011, after more than 30 years of service, America's space shuttle will take to the skies for the last time. Its story has been characterised by incredible triumphs, but blighted by devastating tragedies - and the BBC and Horizon have chronicled every step of its career. This unique and poignant Horizon Guide brings together coverage from three decades of programmes to present a biography of the shuttle and to ask what its legacy will be. Will it be remembered as an impressive chapter in human space exploration, or as a fatally flawed white elephant?

Our understanding of the world around us is better now than ever before. But are we any closer to knowing how its all going to end? Dallas Campbell delves into the Horizon archive to discover how scientists have tried to predict an impending apocalypse - from natural disaster to killer disease to asteroid impact - and to ask: when Armageddon arrives, will science be able to save us?

Child psychologist Laverne Antrobus delves into the Horizon archive to find out how science has shaped our approach to parenting and education over the last fifty years. From lessons in motherly love to tough discipline to bribery tactics, she asks what's the best approach when it comes to bringing up children. Laverne also explores how extreme behaviour can sometimes be explained by underlying neurological problems and discovers whether children learn best in a more child-centred environment.

Dallas Campbell explores how mankind's understanding of dinosaurs has developed since the 1970s. He reveals how technological advances led to scientists revising their theories about how the creatures might have lived, as well as gaining new insights into the reasons for their extinction. The presenter also explores the genetic links between modern birds and the prehistoric lizards.

Horizon goes behind the scenes at CERN to follow one of the most epic and expensive scientific quests of all time: the search for the Higgs particle, believed to give mass to everything in our universe. However, the hunt for Higgs is part of a much grander search for how the universe works. It promises to help answer questions like why we exist and is a vital part of a Grand Unified Theory of nature. At the heart of the pursuit of the elusive particle is the same feature that makes snowflakes beautiful and human faces attractive: the simple and enchanting idea of symmetry.

Dallas Campbell looks back through the Horizon archives to find out what science can tell us about our best friend the dog, and whether new thinking should change the way we treat them. From investigating the domestic dog's wild wolf origins to discovering the remarkable impact that humans have had on canine evolution, Dallas explores why our bond with dogs is so strong and how we can best use that to manage them.

Marcus Du Sautoy wants to find out how close we are to creating machines that can think like us: robots or computers that have artificial intelligence. His journey takes him to a strange and bizarre world where AI is now taking shape. Marcus meets two robots who are developing their own private language, and attempts to communicate to them. He discovers how a super computer beat humans at one of the toughest quiz shows on the planet, Jeopardy. And finds out if machines can have creativity and intuition like us. Marcus is worried that if machines can think like us, then he will be out of business. But his conclusion is that AI machines may surprise us with their own distinct way of thinking.

Engineer Jem Stansfield looks back through the Horizon archives to find out how scientists have come to understand and manipulate the materials that built the modern world. Whether it is uncovering new materials or finding fresh uses for those man has known about for centuries, each breakthrough offers a tantalising glimpse of the holy grail of materials science - a substance that is cheap to produce and has the potential to change the world. Jem explores how a series of extraordinary advances has done just that - from superconductors to the silicon revolution.

Kevin Fong looks back through 40 years of Horizon archives to explore what science has revealed about methods of perception. He discovers why babies use touch more than any other sense, how vision can easily be tricked, and the ways technological advancements are getting closer to being able to replace human faculties if they fail.

Is there any way to slow or even prevent the ravages of time? Veteran presenter Johnny Ball looks back over the 45 years that Horizon - and he - have been on air to find out what science has learned about how and why we grow old. Charting developments from macabre early claims of rejuvenation to the latest cutting-edge breakthroughs, Johnny discovers the sense of a personal mission that drives many scientists and asks whether we are really any closer to achieving the dream of immortality.

Horizon goes behind the scenes at NASA as they countdown to the landing of a 2.5 billion-dollar rover on the surface of Mars. In six days time, the nuclear-powered vehicle - the size of a car - will be winched down onto the surface of the Red Planet from a rocket-powered crane. That's if things go according to plan: Mars has become known as the Bermuda Triangle of space because so many missions there have ended in failure. The Curiosity mission is the most audacious - and expensive - attempt to answer the question: is there life on Mars?

Dallas Campbell looks back through almost 50 years of the Horizon archives to chart the scientific breakthroughs that have transformed our understanding of the universe. From Einstein's concept of spacetime to alien planets and extra dimensions, science has revealed a cosmos that is more bizarre and more spectacular than could have ever been imagined. But with every breakthrough, even more intriguing mysteries that lie beyond are found. This great journey of discovery is only just beginning.

On a bright, cold morning on 15th February 2013, a meteorite ripped across the skies above the Ural mountains in Russia, distintegrating into three pieces and exploding with the force of 20 Hiroshimas. It was a stark reminder that the Earth's journey through space is fraught with danger. A day later, another much larger 143,000-tonne asteroid passed within just 17,000 miles of the Earth. Presented by Professor Iain Stewart, this film explores what meteorites and asteroids are, where they come from, the danger they pose and the role they have played in Earth's history.

Transplant surgery has now reached incredible heights, from achieving full face transplants to growing organs in the lab. This Horizon Guide looks back at the extraordinary odds doctors and patients have had to overcome to achieve these amazing breakthroughs. What we now take for granted has been a hard won struggle, both for the patients who were willing to gamble their lives and the doctors who faced ethical and medical dilemmas in the name of progress. Michael Mosley looks through the Horizon archive, identifying the key turning points for transplant surgery to explore how far science can go in its bid to prolong life.

Liz Bonnin delves in to the world of invention, revealing the people and technologies set to transform all our lives. She examines the conditions that are promising to make the 21st century a golden age of innovation and meets some of the world's foremost visionaries, mavericks and dreamers.

Changes in the weather, pesticides, and even a virus have all all been blamed for the ongoing mass deaths of bees Bill Turnbull meets the scientists who are fitting minute radar transponders on to bees to try to find answers.

It was hoped that Comet ISON could be the brightest and most spectacular comet for a generation. After travelling towards the sun for ten thousand years, it appeared to have been disintegrated by the heat and tidal forces of the sun in early December 2013. But ISON's tail of vapourised gas and water, hundreds of millions of kilometres long, may give insights into some of the greatest mysteries of science.

To celebrate its 50th birthday, Horizon invites the public to play a role in tackling the greatest challenges facing science today. This special episode of Horizon launches the £10 million Longitude Prize 2014 - a prize developed by Nesta, with Technology Strategy Board as funding partner, to find solutions to a new scientific challenge.

Liz Bonnin presents a Horizon special about a rare and beautiful event in our solar system, one that we should all be able to see for ourselves - the transit of Venus across the face of the sun. It will start just before midnight of the 5th of June, and won't happen again for more than a century.

Something peculiar has happened to Britain's weather. During the last two months we have heard frequent stories of forest fires, dried-up reservoirs and even rumours of water rationing. How much of it is true and what is the meaning of the present scare? This special report goes behind the scenes and observes that we are indeed facing the worst drought for over 200 years.

Horizon theorizes how life could be in 2002, using extracts from previous Horizon episodes.

Darwin's theory of evolution transformed our view of the world. But what would he think of the progress we have made since?

An updated report on AIDS, a catastrophic collapse of the immune system that leads to a bizarre range of cancers and potentially fatal infections.

A Horizon special dramatizing the race at the University of Cambridge in 1951 for the discovery of DNA.

Alice Roberts looks through 45 years of Horizon archive material to see how science came to understand sex, strived to solve our problems with it and even helped us do it better.

Dr Helen Czerski delves into the Horizon archive to chart the transformation of a little-known theory into one of the greatest scientific undertakings in history.

Michael Mosley uses the BBC archives to chart scientists' progress as they probed the mind of the murderer to try to understand why people kill, and whether it can help prevent it.

Documentary looking at the perception of AI from 1964 to the present day. Can we be optimistic about all that AI can deliver - or fearful of its ability to control our lives?

Astronaut Tim Peake's video diary of the two years leading up to his arrival at the International Space Station in December 2015.

Comedian Jimmy Carr takes over Horizon for this one-off special programme, produced as part of BBC2's sitcom season. Jimmy turns venerable documentary strand Horizon into a chat show, with eminent laughter scientists as guests and a studio audience to use as guinea pigs. Jimmy and his guests try to get to the bottom of what laughter is, why we enjoy it so much and what, if anything, it has to do with comedy. Between them, and with the help of contributions from other scientists on film, Jimmy and guests discover that laughter is much older than our species, and may well have contributed to making us human. With professors Sophie Scott, Robin Dunbar and Peter McGraw.

The extraordinary inside story of the biggest scientific challenge of our age - following a small band of vaccine scientists around the world who took on Covid-19 and ultimately delivered the weapon to beat it. As news of the coronavirus broke around the globe, a small group of scientists jumped into action to tackle one of the greatest medical challenges of our time: to create a vaccine against a virus no-one had ever seen before and to do so in record time, all during a deadly, global pandemic. English

The Life and Times of El Niño combines history and science to show how this meteorological monster has affected global economy and political history. As a little understood climatic event, El Niño has caused the worst ever yellow fever epidemic in America, cannibalism in China, and in more recent times, the erosion of the coral reef in Australia and severe flooding in Brazil. But, as our knowledge of El Niño grows and attempts are made to predict its worldwide effects, The Life and Times of El Niño asks - could the power of one of nature's most destructive occurrences ever be contained? The Life and Times of El Niño is a science education resource investigating both the history and science of this climatic event.

It's a macabre paradox, but almost every advance in aviation safety has been driven by a crash. After every crash, investigators determine its cause and scientists make every effort to ensure the same mistakes never happen again. Dallas Campbell delves into the Horizon archives to chart the deadly disasters that have helped make air travel today the safest it has ever been.

In the 1950s up to 8,000 people died every year on the roads in this country - a truly horrific figure. Thankfully it has now fallen to around 2,000 a year - still a terrible toll, but a vast improvement, particularly given the increase in cars on the road. Dallas Campbell looks back over decades of Horizon and BBC archive to chart the key scientific breakthroughs that have transformed road safety and saved millions of lives. However, it hasn't all been about innovative engineering and groundbreaking medical discoveries - scientists have also had to act as campaigners, persuading car manufacturers to install their life saving devices and urging the public to use them.

Playful pets, fearsome fighters or deadly hunters? Millions of us have cats in our homes, yet we know very little about them. In this series, Liz Bonnin joins forces with some of the world's top cat experts to conduct a groundbreaking scientific study. With GPS trackers and cat cameras, we follow 100 cats in three very different environments to find out what they get up to when they leave the cat flap. In the first programme we discover how our cats see, hear and smell the world with the senses of their wild ancestors, and why this could be making life difficult for them in the modern world.

The second episode of this unique scientific study reveals the wild side of pet cats. Using GPS trackers and cat cameras, they show how these felines transform from pampered pet to purring predator as soon as they leave the cat flap. Liz Bonnin and some of the world's top cat experts put Ozzy and Smudge under surveillance to find out who is king of the street and reveal why, no matter how hard we try, we can't keep our cats' hunting instincts under control.

In the final episode of this groundbreaking scientific study, Liz Bonnin and a team of scientists reveal the secret language of our cats, the surprising conversations they have when we are asleep, and why they meow to us but not each other. We rig a house with cameras and cat trackers to discover if four cats living under one roof all get on as well as we would like to think. And we find out why living alongside us is making life difficult for our 21st-century cats.

Instead of reaching for the latest fad diet, the best way to lose weight successfully is a personalised approach - diets tailored to your individual biology and psychology. In a groundbreaking national experiment, Dr Chris van Tulleken and Professor Tanya Byron join a team of leading experts to put 75 overweight volunteers on diets designed to tackle the specific reasons why they eat too much. The volunteers are put through a series of tests at a residential clinic to understand how their genes, hormones and psychology influence their eating behaviour. They are then put on the diets the experts believe are best suited to them. Can science succeed where other diets have failed?

It is time to see if personalised dieting will work in normal life. The volunteers have been given one of three diets to follow - based on their genes, their hormones and their psychology. But now they are back at home, trying to stick to their personalised diets with all the stresses and temptations of real life. Dr Chris van Tulleken and Professor Tanya Byron discover how our genetic makeup can make temptation difficult to resist, how understanding the brain reveals what makes us comfort eat and what science can tell us about why we make disastrous food choices.

So far the volunteers have successfully been losing lost weight, but now the honeymoon period is over. It is the final two months of the diet, and their minds and bodies are fighting back. Dr Chris van Tulleken and Professor Tanya Byron find out if the new personalised diets will help them stay on course, and the experts reveal the scientific secrets to permanent dieting success.

Professor Brian Cox takes a journey through the BBC science archive to explore the story of mankind's relationship with the moon, from James Burke testing Nasa equipment to Neil Armstrong's first steps on the lunar surface and the dramatic tale of Apollo 13. He also asks whether international competition could help reignite the public's enthusiasm for space travel and bring about the dawn of a new space age.

In an intensely personal and often surprising film for BBC Two, Alastair Campbell candidly talks about his experience living with depression and explores if radical new treatments can make a difference. Alastair is best known for his role as Tony Blair’s formidable and often contentious spin doctor, but, away from the public eye, he has been dogged by crippling bouts of depression for most of his life. Some days, just getting out of bed is too hard. Therapy and anti-depressant medication is helping him keep his head above water, but is that really the best he can hope for? Encouraged by his family, Alastair sets out on a journey to explore if cutting edge science can offer him - and the millions of people like him - the hope of one day living depression-free. As he tries to understand his depression better, he also reflects on key events in his life and asks if they could have had a negative effect on his mind.

BBC weatherman Peter Gibbs makes an emotional return to Antarctica, years after he lived and worked at the British Antarctic Survey's Halley Research Station. (Part One as shown on BBC News)

BBC weatherman Peter Gibbs's return to Antarctica becomes something of a rescue mission. The British Antarctic Survey reveals how it will save the Halley Research Station from being cast adrift on an iceberg. (Part Two as shown on BBC News)

Investigating the scientific facts and figures behind the biggest public health crisis in living memory as a new coronavirus takes an unprepared world by storm.

Dr Chris van Tulleken, Dr Hannah Fry and Michael Mosley examine the latest research and explore some of the big questions about the new coronavirus and the pandemic it has created.

In this third Horizon special, Dr Chris Van Tulleken is joined by his brother Xand and Dr Guddi Singh to take us through the latest developments and answer current concerns. Though the effect of the coronavirus pandemic has been devastating to many, the team reveal the breakthroughs in genetics, medicine and modelling that have provided a way out of this situation and given hope and confidence that, in the event of a future pandemic, we can take it on and win.

The extraordinary inside story of the biggest scientific challenge of our age - following a small band of vaccine scientists around the world who took on Covid-19 and ultimately delivered the weapon to beat it. As news of the coronavirus broke around the globe, a small group of scientists jumped into action to tackle one of the greatest medical challenges of our time: to create a vaccine against a virus no-one had ever seen before and to do so in record time, all during a deadly, global pandemic.