Aliens In America: Experts investigate strange carvings from 8,000 BC and unexplained sightings in the New World. Is there more to the US's past than history books suggest? (S6, ep 4)
Strange Abductions: Experts scrutinise The Bible for evidence of alien abductions. Could extraterrestrials have been kidnapping humans for thousands of years? (S5, ep 4)
Aliens And Mega-Disasters: Did Mother Nature cause the volcanoes, earthquakes and floods of ancient times? Or could aliens have been responsible? Experts investigate. (S4, ep 4)
Aliens And Temples Of Gold: Experts examine beliefs that a French church provides a gateway to another universe. Plus, could the Sphinx be built on a library left by aliens? (S3, ep 4)
Aliens Contacts: Could aliens have told Joan of Arc how to beat the English army? And could a US serviceman have received a message when he touched a spaceship? Experts investigate.
NASA's Secret Agenda: Experts investigate whether rocket scientist Wernher von Braun might have found inspiration in technology found at the alleged UFO crash in Roswell. (S8, ep 3)
Forbidden Caves: Could Earth's deepest caves hide secret conduits to other worlds? Or harbour evidence that aliens once visited our planet? Experts investigate. (S7, ep 3)
Aliens And Mysterious Mountains: Throughout time, people have believed mountains were the home of the divine. But could these hilltop spirits have been extraterrestrials? (S6, ep 3)
Beyond Nazca: Ancient alien theorists explore the mysterious phenomena of the Nazca Lines. Could these huge geoglyphs in Southern Peru have an extraterrestrial connection? (S5, ep 3)
The Greys: Experts investigate the 'greys' - mysterious beings with big heads and eyes found carved into rocks. Who are these strange figures and what inspired them? (S4, ep 3)