Richard Hammond - TV presenter and self-confessed mystery addict - is on a quest to uncover the truth behind the rumours and whispers around some of the world's strangest alien encounters.
Have you ever spotted a UFO? Are you in danger of alien abduction? And what did happen at Roswell?
Don't miss this instalment in the incredible series by Britain's best-loved TV personality. Explore the world's greatest mysteries - all from the comfort of your armchair!