Tonight on Ancient Aliens the show looks at whether the infamous Roswell incident is just the tip of a conspiracy iceberg.
Back in 1947 the local Roswell Army Air Field (RAAF) in New Mexico issued a press release saying they had recovered parts of a flying disc, which had crashed in a nearby ranch.
The local press ran the story but soon the United States Air Force released its own press statement clarifying that the wreckage was that of a weather balloon.
Decades later they released further classified information saying it was all part of Project Mogul, which was using advanced microphones attached to high altitude balloons to listen for Soviet nuclear weapon testing — with the project being abandoned when more reliable techniques were discovered.
However, many Ancient Astronaut theorists and UFO conspiracy experts believe that the whole thing was a very elaborate misinformation campaign, designed to hide the truth from the public.
They believe the government recovered both alien craft and possibly aliens themselves from the crash. Some even think a few of them might have survived.
Believers point to the FBI memo to J. Edgar Hoover, which is claimed to mention three flying saucers being recovered.
They also say the advancements in stealth and other high-end military tech is down to information gathered from studying these craft.
Outside of the USA experts point to similar crashes and possible recoveries. Some think the new high-powered radars being used by the USA, Soviets and British at the time led to a spate of UFO crashes, before the alien ships were adapted to deal with our advancements in technology.
Kapustin Yar documentary
They also point out that in the few decades since, science has advanced many times faster than it has for thousands of years.
Are there alien craft and perhaps remains stored in Area 51, Pine Gap in Australia, Rudloe Manor in the UK and Kapustin Yar in Russia?
Ancient Aliens preview
Tune in for Ancient Alien – Beyond Roswell tonight at 9pm on History.