While filming new BBC Three series UFO: Conspiracy Road Trip, Irish comedian Andrew Maxwell and UFO expert Darren Perks tried to get into the site.
However, they were stopped by guards armed with M16 machine guns and forced to lie face-down for three hours while authorities checked their credentials.
The 12-strong crew had visited the infamous Area 51 site in Nevada looking for evidence that a flying saucer and even alien bodies had been held there by the US military since the 1940s.
It was as they crossed the border into the site that they were arrested by military officers, who confiscated their phones, wallets and identification.
Speaking to the Daily Mail, Perks said that they had been filming for half an hour at what is known as the 'Back Gate' of Area 51, when they decided to walk past the barriers and into the restricted area.
"We filmed again for another 30 minutes and even messed around doing a silly dance, but still no guards," he said.
"Then one of the other stars of the trip pointed out that on looking through one of the security hut windows, she could see the guards all sitting down eating dinner and watching the basketball game on TV. They did nothing.
"So after a few more minutes and a few more picture taking and filming, one of the crew decided to speak to the guards and knocked on their hut door. All hell broke loose.
"The guards rushed out with their weapons and forced us all to lay face down at gunpoint in the tarmac. We were all searched, had our phones, wallets and IDs taken and the film equipment taken. This was at approx 6.15pm."
The group were held face down for three hours until the Lincoln County Sheriffs arrived on the scene. At that stage, Perks said that things "eased off a bit" and they were taken off the restricted area, processed and fined £375 each.
"We were told that this incident was so serious that Washington had to call London to advise that 12 'Brits' had just breached security at America's most top-secret military base and that we all were at one point going to jail for six months. Luckily whoever it was in Washington was kind enough to just fine us," he said.
"As time went on into the evening at approximately 11pm we were allowed to stand around together while things were signed off to let us go.
"At this point I managed to talk to the guards a bit and one told me how they could 'make you disappear and your body will never be found'."
The group was allowed to leave the site at 11.30pm local time, but said that they were followed by government vehicles right into the following day.
The new three-part series of UFO: Conspiracy Road Trip will debut on BBC Three on Monday, October 15 at 9pm.