Time travel is not forbidden by the laws of nature, but to build a time machine, we would need to understand more about those laws and how to subvert them than we do now. And every day, science does learn more. In this film Horizon meets the scientists working on the cutting edge of discovery - men and women who may discover how to build wormholes, manipulate entangled photons or build fully functioning time crystals. In short, these scientists may enable an engineer of the future to do what we have so far been only able to imagine - to build a machine that allows us travel back and forward in time at the touch of a button. It could be you! Science fiction? Watch this film.

Psychopaths have long captured the public imagination. Painted as charismatic, violent predators lacking in all empathy, they provide intrigue and horror in equal measure. But what precisely is a psychopath? What is it that drives them to cause harm, even kill? And can they ever be cured? The film also features a series of candid interviews with prison inmates who not only describe their crimes but why they think they committed them.
'What Makes a Psychopath?' explores not only how each individual's crimes were shaped by their own life experiences, but also gives an insight into how these people think and behave. Working with the world's experts in the field, the film sheds light on the biological, psychological and environmental influences that shape a psychopath. And it looks to the future, with ground-breaking research that suggests a lifetime of incarceration is not the only option to manage violent and dangerous psychopaths.

We humans often like to think we're the end of the line when it comes to evolution. But if we rewind through our short time on Earth as a species, and the many changes that have occurred to us along the way, we find we're still very much a work in progress. Renowned geneticist and author Spencer Wells reveals how changes in our genetic code have fuelled major changes in our appearance and capabilities over time, and why scientists believe we're continuing to rapidly evolve today. By understanding these changes, we are better prepared for the future.

Launched in 1982 by three friends in a Houston diner, Compaq Computer set out to build a portable PC to take on IBM, the world's most powerful tech company. Many had tried cloning the industry leader's code, only to be trounced by IBM and its high-priced lawyers. 'Silicon Cowboys' explores the remarkable David vs. Goliath story, and eventual demise, of Compaq, an unlikely upstart who altered the future of computing and helped shape the world as we know it today. Directed by Oscar (R)-nominated director Jason Cohen, the film offers a fresh look at the explosive rise of the 1980's PC industry and is a refreshing alternative to the familiar narratives of Jobs, Gates, and Zuckerberg.

Electricity is not just something that creates heat and light, it connects the world through networks and broadcasting. After centuries of man's experiments with electricity, the final episode tells the story of how a new age of real understanding dawned - how we discovered electric fields and electromagnetic waves. Today we can hardly imagine life without electricity - it defines our era. As our understanding of it has increased so has our reliance upon it, and today we are on the brink of a new breakthrough, because if we can understand the secret of electrical superconductivity, we could once again transform the world.

Take a look back at many of the most fascinating science stories of 2017, a year full of stunning advancements in individual fields of study, from astronomy to biology, geology to history – when we piece these discoveries together we see the year in a new light.