Seasons & episodes

A simple virus that started in the belly of a dead bird is set to embark on a global killing spree. H5N1 - a bird flu virus with the potential to become humanised and mutate into the next pandemic flu virus. Horizon explores what could happen if a flu pandemic hits. The last flu pandemic in 1918 killed an estimated 50 million people worldwide. A virus today can spread much easier, much faster and there are estimates that hundreds of millions could be infected and potentially die.

Clouds of alien life forms are sweeping through outer space and infecting planets with life – it may not be as far-fetched as it sounds. The idea that life on Earth came from another planet has been around as a modern scientific theory since the 1960s when it was proposed by Fred Hoyle and Chandra Wickramasinghe. At the time they were ridiculed for their idea – known as panspermia. But now, with growing evidence, it's back in vogue and even being studied by NASA. Horizon meets the scientists on a mission to get to the bottom of the beginnings of life on Earth - from the team in Texas who are lovingly building a robotic submarine called DEPTHX to explore a moon of Jupiter, to Southern India where they are investigating a mysterious red rain which fell for two months in 2001. According to local scientist Godfrey Louis, the rain contains biological cells unlike any he had seen before – with no DNA and the ability to replicate at 300°C. Louis has come to the conclusion that the cells are extra-terrestrial in origin.

What if dinosaurs were still alive today? Would we hunt them, farm them - or even keep them as pets? It's a palaeontologist's dream: the chance to live in a world where dinosaurs are not something to be dug out of the ground but are living among us. It may sound far-fetched but dinosaurs were actually rather unlucky. The meteorite impact that doomed them to extinction was an event with a probability of millions to one. What if the meteorite had missed? Had dinosaurs survived, the world today would be very different. If humans managed to survive alongside them, we wouldn't have the company of most, if not all, of the mammals with which we are familiar today. Giraffes, elephants and other mammals wouldn't have had space to evolve. Would we be hunting Hadrosaurs instead of elk? Or farming Protoceratops instead of pigs? Would dinosaurs be kept as pets? And could the brighter dinosaurs have evolved into something humanoid?

How do you save an endangered species? Get the animals in the mood for love. Thomas Hildebrandt possesses one of the world's most extraordinary jobs - getting the planet's endangered animals in the mood for love. The planet's creatures are facing the biggest mass extinction since the dinosaurs were wiped out. Species are currently disappearing at up to 10,000 times the natural rate. Coming to the rescue are men like Dr Hildebrandt and his team. They are world leaders in the art of animal manipulation. The billions of pounds spent benefiting human reproduction are now being applied to save endangered species. Techniques such as artificial insemination and IVF have been crucial to the successes in breeding giant pandas, big cats and other mammals in zoos across the world. As Thomas Hildebrandt says "Man has created this annihilation of species. It's up to man to use his ingenuity to save them."

Professor Lesley Regan is on a mission to fill her bathroom cabinet with cosmetics that actually work. Professor Lesley Regan, one of the UK's most well-respected (and glamorous) medical experts, turns her scientific eye on the world of cosmetics. She's just turned 50, and is out to create an experimentally proven beauty cabinet. Unafraid to examine the wrinkles, age spots and broken veins on her own face, Professor Regan explores just what makes us look old, and if we can slow down the ageing process. The extraordinary world of cosmetic testing is revealed, from the British hair lab which makes New York tap water, to the volunteers sun-bathing for science. Sun damage, cellulite and balding all face Professor Regan's scrutiny as she discovers which cosmetics do - and don't - have the scientific evidence to back up their claims.

Pianist Nick van Bloss has Tourette's syndrome. Is his illness a blessing or a curse? Is there really such a thing as the mad genius? Can an illness be both a blessing and a curse? At seven years old, Nick van Bloss started shaking his head, grinding his teeth and making wild whooping noises. Nick had Tourette's syndrome. No medical intervention helped him. But one activity stopped it all... The moment Nick placed his hands on the piano keys his symptoms vanished. By the age of 20, he was an award winning international pianist. He felt sure that his illness had made him the success he was. But there is a catch. The brain state necessary for his genius can also be dangerously close to mental chaos. Nick's personal journey reveals how close he came to the edge and how determined he is to triumph.

After 40 years, man is preparing to return to the Moon. But this time the astronauts won't just land on the Moon - they plan to stay. From his office in Nevada, Dennis Hope has spawned a multi-million dollar business selling lunar real estate. But scientists believe the real prize is trapped in the Moon's rocks. It contains large deposits of an extremely rare gas called Helium-3. Could Helium-3 be mined and used as a new source of almost inexhaustible, clean and pollution-free energy on Earth? Whoever succeeds in transporting Helium-3 back to Earth could solve the world's energy crisis. Who will win what has been dubbed the second Moon race? And should we be exploiting the Moon's valuable resources at all?

Seven high-flyers are put through a series of tests to measure their intelligence Can you think of 100 different uses for a sock? How would you cope with glasses that turn everything upside down? What's your emotional intelligence? Can you create a work of art in ten minutes? Horizon takes seven people who are some of the highest flyers in their field - a musical prodigy, a quantum physicist, an artist, a dramatist, an RAF fighter pilot, a chess grandmaster and a Wall Street trader. Each is put through a series of tests to discover who is the most intelligent? The principle way that we measure intelligence, the IQ test, remains popular and convenient. Yet most psychologists agree that it only tells half the story... at most. Where they disagree is how to measure intelligence, for the simple reason that the experts still don't know exactly what it is.

Could Professor Jose Torero's fire protection system have saved the Twin Towers? When a fire gets out of control in a skyscraper it tests fire fighters to their limits. Predicting how a fire is behaving high up in a building is almost impossible. The fire fighters who entered the Twin Towers on 11 September 2001 could only guess at what was happening almost 1000 feet above them. That fateful day brought about the death of 343 New York fire fighters. Jose Torero believes fire fighters need not be put in such danger and that new technology could have saved many of the 343 fire fighters who died doing their duty that day. He believes he could even have saved the Twin Towers. He has spent the last ten years developing a system that could change the way fires are fought forever. It's called Firegrid. It's a revolutionary approach to fire fighting that could save thousands of lives, giving man the upper hand on one of his oldest enemies.

Will the Large Hadron Collider finally reveal the elusive God particle? In the coming months the most complex scientific instrument ever built will be switched on. The Large Hadron Collider promises to recreate the conditions right after the Big Bang. By revisiting the beginning of time, scientists hope to unravel some of the deepest secrets of our Universe. Within these first few moments the building blocks of the Universe were created. The search for these fundamental particles has occupied scientists for decades but there remains one particle that has stubbornly refused to appear in any experiment. The Higgs Boson is so crucial to our understanding of the Universe that it has been dubbed the God particle. It explains how fundamental particles acquire mass, or as one scientist plainly states: "It is what makes stuff stuff..."

Is it possible to use a knowledge of forensic science, not to catch a killer, but to commit a perfect murder? Modern forensic science should make it impossible to commit murder and get away with it. But how easy would it be to outfox the detectives? With the help of top forensic scientists, and real-life murder investigations, we explore whether it's possible to commit a perfect murder. The body is the most important piece of evidence in any murder. Pathologist Dr Richard Shepherd reveals the crucial clues that give away the secrets of a suspicious death. Dr Lee Goff can work out a time of death from just a few maggots on a corpse. To really understand the way a human decomposes he relies on experiments - and dead pigs make ideal human models. And what is the perfect murder weapon? Probably Agatha Christie's favourite - poison. It leaves no marks on the body, and the victim may not even realise what has happened until it's too late. But there still might not be a perfect murder. The world's most notorious poisoner - Harold Shipman - was eventually caught.

Michael Portillo looks at the science behind executions. Former Conservative MP, Michael Portillo pushes his body to the brink of death in an investigation into the science of execution. As the American Supreme Court examines whether the lethal injection is causing prisoners to die in unnecessary pain Michael sets out to find a solution which is fundamentally humane. To do so he examines the key methods of execution available today: he discovers why convicts can catch on fire in the electric chair, learns how easy it is to botch a hanging and inhales a noxious gas to experience first hand the terror of the gas chamber. Armed with some startling evidence Michael considers a completely new approach. Will it be the answer? There is only one way of finding out - to experience it himself.

Psychologists subject six volunteers to a world without stimulation. For the first time in 40 years Horizon re-creates a controversial sensory deprivation experiment. Six ordinary people are taken to a nuclear bunker and left alone for 48 hours. Three subjects are left alone in dark, sound-proofed rooms, while the other three are given goggles and foam cuffs, while white noise is piped into their ears. The original experiments carried out in the 1950s and 60s by leading psychologist Prof Donald Hebb, was thought by many in the North American political and scientific establishment to be too cruel and were discontinued. Prof Ian Robbins, head of trauma psychology at St George's Hospital, Tooting, has been treating some of the British Guantanamo detainees and the victims of torture who come to the UK from across the world. Now he evaluates the volunteers as their brains undergo strange alterations.

Dr Brian Cox wants to know why the Universe is built the way it is. Particle physicist and ex D:Ream keyboard player Dr Brian Cox wants to know why the Universe is built the way it is. He believes the answers lie in the force of gravity. But Newton thought gravity was powered by God, and even Einstein failed to completely solve it. Heading out with his film crew on a road trip across the USA, Brian fires lasers at the moon in Texas, goes mad in the desert in Arizona, encounters the bending of space and time at a maximum security military base, tries to detect ripples in our reality in the swamps of Louisiana and searches for hidden dimensions just outside Chicago.

A trip through the highs and lows of the UK’s 20 most dangerous drugs. Recent research has analysed the link between the harmful effects of drugs relative to their current classification by law with some startling conclusions. Perhaps most startling of all is that alcohol, solvents and tobacco (all unclassified drugs) are rated more dangerous than ecstasy, 4-MTA and LSD (all class A drugs). If the current ABC system is retained, alcohol would be rated a class A drug and tobacco class B. The scientists involved, including members of the government's top advisory committee on drug classification, have produced a rigorous assessment of the social and individual harm caused by 20 of the UK's most dangerous drugs and believe this should form the basis of future ranking. They think the current ABC system is arbitrary and not based on any scientific evidence. The drug policies have remained unchanged over the last 40 years so should they be reformed in the light of new research?

Lifting the lid on the business of human choices in an exclusive guide to making better decisions. We are bad at making decisions. According to science, our decisions are based on oversimplification, laziness and prejudice. And that's assuming that we haven't already been hijacked by our surroundings or led astray by our subconscious! Featuring exclusive footage of experiments that show how our choices can be confounded by temperature, warped by post-rationalisation and even manipulated by the future, Horizon presents a guide to better decision making, and introduces you to Mathematician Garth Sundem, who is convinced that conclusions can best be reached using simple maths and a pencil!

While scientists have been searching for the secrets of long life, a few isolated communities have stumbled across the answer. The quest to live longer has been one of humanities oldest dreams, but while scientists have been searching, a few isolated communities have stumbled across the answer. On the remote Japanese island of Okinawa, In the Californian town of Loma Linda and in the mountains of Sardinia people live longer than anywhere else on earth. In these unique communities a group of scientists have dedicated their lives to trying to uncover their secrets. Horizon takes a trip around the globe to meet the people who can show us all how to live longer, healthier lives.

Friendly bacteria, superfoods, cholesterol busting spreads, 99% germ free, whiter than white...it's almost impossible to find a product in the supermarket today that doesn't come with impressive claims...a scientific claims, but do they actually do what they say? Are they worth the price? Are they worth a place in Prof. Regan's shopping trolly?

Use the Drake equation to calculate the number of civilisations in our galaxy. For fifty years, the Search for Extra Terrestrial Intelligence has been scanning the galaxy for a message from an alien civilisation. So far to no avail, but a recent breakthrough suggests they may one day succeed. Horizon joins the planet hunters who've discovered a new world called Gliese 581 c. It is the most Earth-like planet yet found around another star and may have habitats capable of supporting life. NASA too hopes to find fifty more Earth-like planets by the end of the decade, all of which dramatically increases the chance that alien life has begun elsewhere in the galaxy.

Horizon investigates the medical revolution that has created an almost insatiable demand for body parts . When veteran broadcaster Alistair Cooke died in 2004 few suspected that he was yet to uncover his greatest story. What happened to his body as it lay in a funeral home would reveal a story of modern day grave robbery and helped smash a body-snatching ring that had made millions of dollars by chopping up and selling-off over 1000 bodies. Dead bodies have become big business. Each year millions of people's lives are improved by the use of tissue from the dead. Bodies are used to supply spare parts, and for surgeons to practice on. Horizon investigates the medical revolution that has created an almost insatiable demand for body parts and uncovers the growing industry and grisly black market that supplies human bodies for a price.

Horizon journeys into the human memory, from how it emerges in childhood, develops through to adulthood, and fades in middle age. You might think that your memory is there to help you remember facts, such as birthdays or shopping lists. If so, you would be very wrong. The ability to travel back in time in your mind is, perhaps, your most remarkable ability, and develops over your lifespan. Horizon takes viewers on an extraordinary journey into the human memory. From the woman who is having her most traumatic memories wiped by a pill, to the man with no memory, this film reveals how these remarkable human stories are transforming our understanding of this unique human ability. The findings reveal the startling truth that everyone is little more than their own memory.

Horizon asks some of the biggest names in science to have a quiet word with the new American president. The United States president is quite simply the most powerful man on earth, but past presidents have often known little about science. That is a problem when the decisions they make will affect every one of us, from nuclear proliferation to climate change. To help the new president get to grips with this intimidating responsibility, some of the world's leading scientists, from Dawkins to Watson, share some crucial words of advice.

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.