The final programme in the series looks at the incredible discoveries of the last 50 years and reveals where some of the greatest minds of our time think we are heading. Richard Dawkins and Olivia Judson reveal the controversial true story of how Rosalind Franklin's work in crystallography helped Watson and Crick to discover the double-helix structure of DNA, and the wealth of knowledge now gathered about the human genetic blueprint as a result. Jim Al-Khalili charts the career of astronomer Fred Hoyle, who helped to popularise science, worked out that we are all made of star-dust and, ironically, coined the term 'Big Bang' for a theory he rejected. James Dyson explores a revolutionary new discovery - carbon nanotubes - which, as well as being the toughest material known to man and 50,000 times thinner than a human hair, offer potential applications from cheap and super-efficient solar power to building a 'space elevator'. To end the series, Stephen Hawking and Richard Dawkins ask each other the questions they really want answered: Is there life on other planets? Why are you so obsessed with God? And all of the scientists explain just why they think science is now more important than ever.