Roses are red, violets are blue but according to the latest understanding these colours are really an illusion. One that you create yourself. Horizon reveals a surprising truth about how we all see the world. You may think a rose is red, the sky is blue and the grass is green, but it now seems that the colours you see may not always be the same as the colours I see. Your age, sex and even mood can affect how you experience colours. Scientists have unlocked the hidden power that colours can have over your life - how red can make you a winner, how blue makes time speed up. Watch an experiment where for people in a blue pod, a minute lasts 11 seconds shorter.

Dr Adam Rutherford shows how decoding the genome has led us to begin to understand the very process by which our DNA makes us different; how it makes each one of us on earth unique and influences who we are and the traits we have. He reveals how, as we try and understand the relationship between who we are and our genes, we stand at the beginning of the most exciting scientific journey of all time.

For centuries scientists have been attempting to come up with an elixir of youth. Now remarkable discoveries are suggesting that ageing is something flexible that can ultimately be manipulated. The scientists are attempting to piece together why we age and more vitally for all of us, what we can do to prevent it. But which theory will prevail? Does the real key to controlling how we age lie with a five-year-old boy with an extraordinary ageing disease or with a self-experimenting Harvard professor? Could one of these breakthroughs really see our lives extend past 120 years?

Horizon explores the strange and wonderful world of illusions – and reveals the tricks they play on our senses and why they fool us. We show how easy it is to trick your sense of taste by changing the colours of food and drink, explain how what you see can change what you hear, and see just how unreliable our sense of colour can be. But all this trickery has a serious purpose. It’s helping scientists to create a new understanding of how our senses work – not as individual senses, but connected together. It holds the intriguing possibility that one sense could be mapped into another.

Over a person's lifetime they are likely to be prescribed more than 14,000 pills. Antibiotics, cholesterol lowering tablets, anti-depressants, painkillers, even tablets to extend youth and improve performance in bed. These drugs perform minor miracles day after day, but how much is really known about them? Drug discovery often owes as much to serendipity as to science, and that means much is learnt about how medicines work, or even what they do, when they're taken. By investigating some of the most popular pills people pop, Horizon asks, how much can they be trusted to do what they are supposed to?

The world stood in fear of an emerging new disease that threatened to kill millions. A new flu variant H1N1 had arrived. If this latest pandemic has taught anything, it is just how little is understood about the invisible world of viruses. But that has not stopped scientists trying. Horizon follows the leading researchers from across the world, who are attempting to unravel the many secrets of viruses to understand when and why they kill.