Ancient Aliens explores the controversial theory that extraterrestrials have visited Earth for millions of years. From the age of the dinosaurs to ancient Egypt, from early cave drawings to continued mass sightings. In this episode researchers discuss the possibility that the great technological developments made by inventor Nikola Tesla were inspired by extraterrestrials

Researchers discuss the possibility that the creation of the Large Hadron Collider was foretold in ancient sources that were inspired by aliens

Researchers discuss mythic ancient treasure and curses including King Solomon's Ring, lost Aztec treasure, and the Omphalos.

What if aliens landed on Earth? Much of science fiction explores the moment of first contact – what will people do when the aliens land? From H. G. Wells’ pioneering The War of the Worlds to Independence Day, Men in Black, and District 9, Invasion deals with our fears of alien invasions of earth. David Tennant explains the appeal of Doctor Who’s Daleks and Cybermen while John Carpenter and Chris Carter explore the rich appeal of the paranoia fuelled by hidden aliens with The Thing and The X-Files. It also asks, what if the monsters were our own creation? With the aid of rarely seen animation tests, Phil Tippett takes us behind the scenes in the creation of the dinosaurs of Jurassic Park. But not all invasions are hostile. Peter Coyote and Richard Dreyfuss discuss the creation of Spielberg’s spellbinding classics E.T. the Extra-Terrestrial and Close Encounters of the Third Kind. There is more than one kind of invasion.

It's a golden age for planet hunters: recently, they've discovered more than 750 planets orbiting stars beyond our sun. Some of them, like a planet called Kepler-22b, might even be able to harbor life. What would that life look like? Combining startling animation with input from expert astrobiologists, Alien Planets Revealed takes viewers on a journey of the imagination as we 'build' aliens from the ground up. What chemical building blocks will make up their genetic code? How will life get started and how will the exotic environment on a planet like Kepler-22b drive evolution? Bringing the creative power of veteran animators together with the latest discoveries in astrobiology, Alien Planets Revealed provides a glimpse of the creatures we might one day encounter beyond our solar system.

Aliens almost certainly do exist. So why haven't we yet met E.T.? It turns out we're only just developing instruments powerful enough to scan for them, and science sophisticated enough to know where to look. As a result, race is on to find the first intelligent aliens. But what would they look like, and how would they interact with us if we met? The answers may come to us sooner than we imagine, for one leading astronomer believes she may already have heard a hint of their first efforts to communicate