Here, Aleks charts how the Web is forging a new brand of politics, both in democracies and authoritarian regimes. With contributions from Al Gore, Martha Lane Fox, Stephen Fry and Bill Gates, Aleks explores how interactive, unmediated sites like Twitter and YouTube have encouraged direct action and politicised young people in unprecedented numbers. Yet, at the same time, the Web's openness enables hardline states to spy and censor, and extremists to threaten with networks of hate and crippling cyber attacks.

The Milky Way, our galaxy, is a magnificent sight in the night sky, but we know surprisingly little about it for certain. What is its shape? How many stars does it actually contain? What lies at its centre? The Gaia space telescope will answer these questions, being armed with the most advanced camera to leave our planet, and it will allow us to see our galaxy as we've never seen it before. The Sky at Night visits the factory in Chelmsford that made the astonishing sensor at the heart of the mission.

Scientific advancements are challenging the concept of what it means to be human. Technology embedded in our bodies is fairly common: artificial limbs, pacemakers. But new research is taking us beyond replacement parts and into a new realm that is changing the nature of the human body and the human mind. Will the fusion of biology and technology change how we think, how we feel, how we experience the world?

The mission of the film is to underline the crucial ecological role of coral reefs play in maintaining the well being of our planet, and to point out and warn against the dangers that are destroying the world's coral reefs. Entirely filmed using digital technology, thanks to it, the film was shot almost entirely with natural light, thus showing the underwater world as it exactly is. This is the closest you can get to dive without being there. Shot on the Great Barrier Reef in Australia and in the Bahamas, it brings to you the amazing beauty of the many varieties of coral and the immense diversity of the marine life thriving there.

The Internet is an uncontrollable labyrinth of content and imagery that operates under loose laws and partial anonymity - a new frontier where people can do anything and see anything, whether they should or not. In this lawless landscape, who's in control? The protectors? The abusers? In this episode meet the content moderators who watch the worst of the Internet so you don't have to; a convicted hacker whose punishment was the virtual prison of the unplugged; plus, a blackhat hacker who encrypts and holds computer files hostage.

Michael Ruppert is an independent journalist who has made a minor career out of telling people news that most folks do not want to know. Ruppert, a former police officer, predicted the Wall Street debacle of 2008 several years before the fact, at a time when most analysts were still imagining infinite growth for the stock market and major investment banks. Since then, his vision of the world's future has grown only darker. As Ruppert sees it, civilization and the global economy has yet to wean itself off fossil fuels, and when the world's supply of oil finally runs out, it will lead to a global financial catastrophe that will leave no one unscathed. But while most of what Ruppert has to say bears the ring of truth, there's a small audience for his dire message -- the primary medium for his work is a self-published newsletter, and his most recent book has done so poorly in the marketplace that he faces eviction from his home. Is Ruppert right? And if he is, why doesn't anyone care? Filmmaker Chris Smith profiles Michael Ruppert and gives him a chance to explain his apocalyptic vision of the future at length