Are we alone or is there other life out there? In this programme we meet the alien hunters, who spend their time tracking down life in the Cosmos. Some of them are looking for incredibly primitive life really close at hand. And others are looking for something you could talk to
ET, Close Encounters, Mars Attacks - the movies are full of extra-terrestrial landings and contact with aliens. In fact, all cultures have represented alien beings in their art, stories and writing at some time or other. But what does science say?