Earth is the most colourful place we know of. But the colours we see are far more complex and fascinating than they appear. In this series, Dr Helen Czerski uncovers what colour is, how it works, and how it has written the story of our planet - from the colours that transformed a dull ball of rock into a vivid jewel to the colours that life has used to survive and thrive". But the story doesn't end there - there are also the colours that we can't see, the ones that lie beyond the rainbow. Each one has a fascinating story to tell. Early Earth was a canvas for the vast new palette of the colours of life, with the diversity of human skin tones telling the story of how humanity spread and ultimately conquered the planet. Dr Helen Czerski explores the true masters of colour - which are often the smallest and most elusive - travelling to the mountains of Tennessee to witness the colourful mating display of fireflies, and revealing the marine creatures that can change the colour of their skin in order to hide from the world.

Iain Stewart investigates a new and controversial energy rush for the natural gas found deep underground. Getting it out of the ground involves hydraulic fracturing - or fracking. We travel to America to find to find out what it is, why it is a potential game changer and what we can learn from the US experience". Sometimes, this is right under the places people live in. He meets some of the people who have become rich from fracking as well as the communities worried about the risks. Director Jeff Wilkinson

More than twenty-five years after the world wide web was created, it is now caught in the greatest controversy of its existence: surveillance. With many concerned that governments and corporations can monitor our every move, we wil meet the hackers and scientists whose technology is fighting back". It is a controversial technology, and some law enforcement officers believe it is leading to 'risk-free crime' on the 'dark web' - a place where almost anything can be bought, from guns and drugs to credit card details. Featuring interviews with the inventor of the world wide web, Sir Tim Berners-Lee, and the co-founder of WikiLeaks, Julian Assange, we delve inside the 'dark web'.

A celebration of the career of the musician, whose death from cancer was announced 11th Jan 2016. Bowie's work was the soundtrack to a generation and influenced countless musicians and this features memorable music videos and performances, as well as tributes from friends and fans around the world". Singer, songwriter, multi-instrumentalist, record producer, painter, and actor. He was a figure in popular music for over five decades, and was considered by critics and other musicians as an innovator, particularly for his work in the 1970s. Bowie's impact was enormous; he changed the nature of rock music, and changed his own approach repeatedly. During his career, he sold an estimated 140 million records worldwide. In the UK, he was awarded nine platinum album certifications, eleven gold and eight silver, and in the US received five platinum and seven gold certifications. He was inducted into the Rock and Roll Hall of Fame in 1996. Bowie stopped concert touring after 2004, and last performed live at a charity event in 2006. In 2013, he returned from a decade-long recording hiatus, remaining musically active until his death from liver cancer three years later.

Of all the wonders of the human body, there's one more mysterious than any other. Blood: five precious litres that keep us alive. Yet how much do we really know about this sticky red substance and its mysterious, life-giving force? Michael Mosley gives up a fifth of his own blood to perform six bold experiments". From starving it of oxygen to injecting it with snake venom, Michael reveals the extraordinary abilities of blood to adapt and keep us alive. Using specialist photography, the programme reveals the beauty in a single drop. Michael even discovers how it tastes when, in a television first, he prepares a black pudding with his own blood. Down the ages, our understanding of blood has been as much myth as science, but Michael reveals there might be truth in the old vampire legends, as he meets one of the scientists behind the latest research that shows young blood might be able to reverse the ageing process - the holy grail of modern medicine.

These unmanned flying robots–some as large as jumbo jets, others as small as birds–do things straight out of science fiction. Much of what it takes to get these robotic airplanes to fly, sense, and kill has remained secret. But now, with rare access to drone engineers and those who fly them for the U.S. military, we reveal the amazing technologies that make drones so powerful". From cameras that can capture every detail of an entire city at a glance to swarming robots that can make decisions on their own to giant air frames that can stay aloft for days on end, drones are changing our relationship to war, surveillance, and each other. And it's just the beginning. Discover the cutting edge technologies that are propelling us toward a new chapter in aviation history