There is a battle playing out inside your body right now. It started billions of years ago and it is still being fought in every one of us every minute of every day. It is the story of a viral infection - the battle for the cell.

This is the epic story of the stars, and how discovering their tale has transformed our own understanding of the universe.

This is the story of the most extraordinary journey in human exploration, the Voyager space mission. In 1977 two unmanned spacecraft were launched by NASA, heading for distant worlds. It would be the first time any man-made object would ever visit the farthest planets of the solar system - Jupiter, Saturn, Neptune and Uranus.

A collection of performances from the BBC archives, celebrating the sights and sounds and the ups and downs of London through the words and songs through the years .

Jools Holland embarks on a personal journey through the streets, historical landmarks, pubs, music halls and rock 'n' roll venues of London to uncover a history of the city through its songs, the people who wrote them and the Londoners who joined in the chorus.

In this one-off documentary, Space Dive tells the behind-the-scenes story of Felix Baumgartner's historic, record-breaking freefall from the edge of space to Earth.

Monterey Bay on California's coast is one of the most diverse marine ecosystems in the world, its giant kelp forest bursting with life, from microscopic plankton to visiting ocean giants. The secret key to success in such a busy microworld is balance. Steve Backshall guides us through the unique geography of the bay and introduces some of its key characters in a quest to find the one species that keeps life in the kelp forest in check.

In a revelatory look at Svalbard, the most northerly region in the series, Steve Backshall leaves no stone unturned as he unravels the secrets that lie covered in ice for most of each year. Svalbard is cold, dark and foreboding, yet it is home to the world's largest land predator and the most northerly population.

What's really going on inside your stomach? In this documentary, Michael Mosley offers up his own guts to find out. Spending the day as an exhibit at the Science Museum in London, he swallows a tiny camera and uses the latest in imaging technology to get a unique view of his innards digesting his food. He discovers pools of concentrated acid and metres of writhing tubing which is home to its own ecosystem.

The heart is the most symbolic organ of the human body. Throughout history it has been seen as the site of our emotions, the very centre of our being. But modern medicine has come to see the heart as just a pump; a brilliant pump, but nothing more. And we see ourselves as ruled by our heads and not our hearts.

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.

Plastic surgeon Dr Rozina Ali leaves the operating theatre behind for the frontiers of skin science and asks if it is possible to make your skin look younger without surgery.

Following a season in which football has been rocked by allegations of racism, former Premier league defender Clarke Carlisle explores how far his profession has really progressed since the dark days of banana throwing on the terraces in this documentary.

Documentary which goes inside the secretive Traveller world - a world of long and bitter memories. Filmed over twelve years, the film chronicles a history of violent feuding between rival families, using remarkable access to document the bare-fist fights between the Quinn McDonaghs and the Joyce clans, who, though cousins, have clashed for generations.

Beautiful and intimate documentary which follows the stories of a group of characters as they live through a dramatic night.

The wild Hamadryas Baboons of Ethiopia have a friend in biologist Mat Pines, they even pick the nits from his hair. He's been studying and living with them for five years in the remote and arid Awash National Park.

Touch, sight, smell, hearing and taste - our senses link us to the outside world. Dr Kevin Fong looks back through 40 years of Horizon archives to find out what science has taught us about our tools of perception - why babies use touch more than any other sense, why our eyes are so easily tricked.

In this documentary, the presenter and art critic Matthew Collings explores how Turner, the artist of light, makes light the vehicle of feeling in his work, and how he found inspiration for that feeling in the waters of the River Thames.

First transmitted in 1988, Arena presents a documentary programme exploring the life of Woody Guthrie, the travelling American singer-songwriter who paved the way for the likes of Bob Dylan and Bruce Springsteen.

Documentary telling the little-known story of how Darwin came to write his great masterpiece, On the Origin of Species, a book which explains the wonderful variety of the natural world as emerging out of death and the struggle of life.

Julien Temple's epic time-travelling voyage to the heart of his hometown. From musicians, writers and artists to dangerous thinkers, political radicals and above all ordinary people, this is the story of London's immigrants, its bohemians and how together they changed the city forever.

In episode one Rory Stewart tells the story of British interventions in Afghanistan in the 19th century, when the British Empire became obsessed with the idea that their rival, Russia, was considering the invasion of Afghanistan as a staging post for an attack on British India.

Rory Stewart tells the story of the Soviet invasion of Afghanistan in the twentieth century, and its parallels with the American-led coalition's intervention today.

1979 film portrait of the late New Wave singer-songwriter, Poly Styrene.

Following the front line of engineering and high-tech construction

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.

A history of one of the world's most challenging mountains, the Eiger, and its infamous north face. The film gets to the heart of one of Europe's most notorious peaks, exploring its character and its impact on the people who climb it and live in its awesome shadow.

Documentary telling the double-edged story of the grave risks we pose to our own survival in the name of progress. With rich imagery the film connects financial collapse, growing inequality and global oligarchy with the sustainability of mankind itself.

On Saturday 12 November 2011 an eclectic range of British people turned the camera on themselves, capturing the entertaining and mundane, the exciting and unusual, the poignant and the everyday.

The day after London won the Olympic bid, terrorists attacked the public transport network killing 52 people and injuring over 700.