Underground Alien Bases: The team investigates rumours of human-alien genetic experiments reportedly going on deep below the New Mexico desert in an underground base. (S3, ep 3)

UFO Emergency: Investigation into a huge pulsating light spotted in the sky near Ohio in 1994. A radar operator describes what he saw. (S2, ep 3)

Reverse Engineering: Has the US military derived various forms of technology, including stealth technology, from downed UFOs? The UFO Magazine team investigate. (S1, ep 3)

Grey's Conspiracy: The team investigates disturbingly similar stories of alien abductions from two different countries before tracking down some potential proof in Mexico. (S3, ep 2)

Heartland Explosion: The team finds new evidence concerning the strange booms and orange lights that panicked Indiana in 2008, disbanding theories it was a military jet. (S2, ep 2)

USOs: The team use high-tech sidescan sonar and deep sea magnetometers to search for evidence after learning of an encounter with an underwater phenomenon. (S1, ep 2)

Giant Triangles: The team uncovers rare footage of floating giant triangles hovering over cities. Could these strange sightings be extraterrestrial in origin? (S3, ep 1)

Invasion Illinois: Series examining UFO sightings, alien abductions and government cover-ups, beginning with an investigation into multiple sightings in Illinois in 2004. (S2, ep 1)

Cops vs UFOs: Hear first-hand accounts from seasoned, decorated police officers who have had unbelievable, but substantiated UFO encounters. (S1, ep 1)

Russian Roswell: An exploration of the facts and myths surrounding the Soviet-era UFO research programmes at Kapustin Yar. (S1, ep 16)