A top-secret US Air Force base has become the focus of some unwanted attention after more than a million people vowed to storm it to uncover alien activity.
So far, 1.2 million people have signed up to the Facebook event on September 20 called "Storm Area 51, they can't stop all of us" as part of a wacky online bid to "see them aliens".
For years Area 51, which is found deep in a remote part of the Nevada Desert, has been the subject of conspiracy theories with many claiming that alien activity takes place there.
Officials say it is merely a top secret air force base in the Nevada Test and Training Range. However, its current use is unknown and operations there remain highly classified.
To add to the intrigue, it was only in 2013 that the CIA officially acknowledged it existed, with the US government denying for years the base existed at all.
Here, we take a look at some of the theories that surround Area 51.
What are the Area 51 conspiracy theories?
Many people believe the US government stores secret information about extra-terrestrial activity, and for decades the site has been the subject of numerous UFO conspiracy theories.
Some even maintain the base is where captured UFOs and alien remains are kept, although the US government has always categorically denied this.
In 1947, a United States Army Air Forces balloon crashed at a ranch near Roswell, New Mexico - but conspiracy theorists believe the vessel was in fact an alien spaceship and was carted off to Area 51 for examination shortly after the crash.
Others claim the government uses the site to develop weather control and time travel along with sci-fi weapons, propulsion systems and aircraft based on alien technology.
Many believe there is an railway serving facilities underground, and that there is a camouflaged runway that only appears when water is sprayed on it.
Alarmingly, some even believe that engineers hold meetings or joint undertakings with aliens at Area 51.
Arguably one of the most bizarre theories is the belief that Area 51 is used as a base for a one world government.
Why do they believe the conspiracy theories?
After years of denying it existed, in 2013 the CIA was forced to acknowledge its existence following a Freedom of Information request filed in 2013.
Its location was finally revealed and the US government admitted it was a military site, but officials never disclosed the type of activity that goes on there.
The base's actual function remains to be a mystery and it is still constantly patrolled by armed guards, CCTV, and motion-sensor cameras.
But the secrecy surrounding the base has prompted scores of people around the world to believe the area is holding more than officials say.
Part of this is down to the sighting of apparent UFOs in the area, with many people in the past claiming to have seen alien aircraft in the skies around the base.
However, many of these supposed UFO sightings can be attributed to top-secret reconnaissance aircraft in the 1950s, specifically the Lockheed U-2 and the SR-71 Blackbird.
Not only did these aircraft have a different shape to many others at the time, but also flew at faster speeds and higher altitudes than most others too.
What was the Roswell incident in 1947?
The hugely controversial and well-known Roswell incident happened in 1947, when a man named William Brazel spotted some debris in the desert in June of that year.
One month later, the military issued a press release announcing that a "flying disc" had been found there.
But the next day the statement was retracted with the air force instead saying it was a damaged weather balloon.
However, it wasn't until the 1990s that the true nature of crashed object was revealed - a nuclear test surveillance balloon from one of the site's top-secret projects.
The military had decided to conceal the true purpose of the crashed balloon for nearly 50 years, with the secrecy leading to many people believing the military was hiding even more than it was letting on and adding further fuel to the ongoing conspiracy theories.
