It shouldn't surprise anyone that there's a top secret base out in the middle of the Nevada desert. After all, advanced military hardware has to be tested somewhere -- why not there?

And it also makes sense that a place like Area 51 would be kept secret, rimmed by severe warning signs to any and all trespassers who attempt to get a closer look at what's being tested in the skies above the base. From a distance, some stealth bomber technology could have been easily taken for UFOs by curiosity seekers.

"The reason why I believe Area 51 is classified to the point of almost absurdity -- when everyone knows it exists -- is a stunning reveal that I write about in the very end of my book," Jacobsen said. "It links directly to the Roswell crash."

In her book, Jacobsen suggests it wasn't an alien spaceship that came down in 1947, sparking decades of speculation of visitors from the stars.

Citing an unnamed government-contracted engineer who spent three decades working for the Atomic Energy Commission and worked at Area 51, Jacobsen writes that the alleged spaceship was, instead, a Soviet spy plane with a crew of malformed adolescents.

As the story goes, former Soviet leader Josef Stalin was impressed by how the 1938 radio broadcast of H.G. Wells' "War of the Worlds" caused many Americans to actually believe an invasion was underway by Martians. With a seized post-World War II German jet-powered aircraft under his control, Stalin allegedly enlisted Josef Mengele, a German SS officer and physician notorious for experimenting on concentration camp inmates, which earned him the nickname "Angel of Death."

In the bizarre tale recounted by Jacobsen, Mengele surgically altered a group of children to look like space aliens. These kids were placed on a remotely controlled disc-shaped craft, presumably to frighten Americans into "War of the World"-type hysterics.

But something went wrong, the plane crashed, and the Roswell legend was born, with "alien" wreckage and bodies sent on to Area 51 -- if you believe that story.

"I researched and fact-checked everything that he told me in our interviews which took place over two years," Jacobsen said. "Everything he said checked out. I have no doubt of the veracity of the story and the reason why it's so explosive.""According to my source, the base actually began operations in 1951 to work on the Roswell remains, and that's why it's called Area 51."