Aliens And The Undead: Experts study previous reports of zombies, vampires and spirits. Could these sightings of the undead actually have been alien encounters? (S3, ep 15)
Tesla Experiment: Inventor Nikola Tesla claimed to have direct communication with beings on other planets. Could this genius scientist have been a human 'receiver'? (S6, ep 14)
The Power Of Three: Experts investigate the power of the number three in history, science and astronomy. Could its huge significance bear links to extraterrestrial life? (S5, ep 14)
Mystery Of Puma Punku: No one knows who designed and built Bolivia's sophisticated temple complex. Could it have been aliens? Experts investigate. (S4, ep 14)
Aliens And The Secret Code: Experts scrutinise prehistoric ruins, asking whether humans could have built these advanced structures alone. Might they have had alien help? (S3, ep 14)
Aliens & Superheroes: Experts investigate whether ancient tales of beings with super-human powers could be inspired by extra-terrestrials who came to Earth in the past. (S6, ep 13)
Crystal Skulls: Experts explore the controversy surrounding the ancient Crystal Skulls, asking what powers might be unleashed if all 13 artefacts were brought together. (S5, ep 13)
Aliens And Dinosaurs: Theorists investigate a depiction of a stegosaurus found at Angkor Wat in Cambodia. Could it suggest that alien species killed off the dinosaurs? (S4, ep 13)
The Alien Agenda: Ancient alien theorists investigate evidence suggesting that extraterrestrials have played a pivotal role in the progress of mankind. (S7, ep 12)
Reptillians: Experts question whether ancient myths provide evidence that reptillian aliens are more than just pop-culture creations and staples of science-fiction. (S6, ep 12)