When rumors swirl around a topic for decades, eventually, someone starts investigating.

In the case of the alleged UFO sighting in Cape Girardeau in April 1941, it was Springfield, Missouri, resident Paul Smith who decided to research the rumors.

"I heard more and more about it, and I began to see references to it in a book or two here and there," he says.

Author Paul Smith (Submitted photo)

Smith was born in Cape Girardeau, where he grew up and graduated from the Hawthorne School, now known as Charles Clippard School. He went on to graduate from Southeast Missouri University.

He says he felt compelled to look into the mysterious incident that took place in his hometown.

Author Paul Smith (submitted photo)

"I began making frequent trips to Cape Girardeau to interview people and to do some snooping," Smith says. "I hit the Internet and began digging into all kinds of books."

The Sci-Fi Channel produced a show, "The Secret: Evidence We are Not Alone," in 2002, which included a brief recreation about what allegedly happened in Cape Girardeau, and it further piqued Smith's interest.

"There is not a single book on this subject," he says.

That will change in April, when Smith's book is scheduled to be released by Argus Publishing.

This year marks the 75th anniversary of the incident that is the topic of his book.

"The date in 2016 is not definite, and they haven't given me a book cover, but we're getting there," he says.

The book, titled "MO41: The Bombshell Before Roswell," is still in the preproduction stage, and the publisher is working on art for illustrations, Smith says.

The research Smith conducted for the book led him to some interesting hypotheses.

For example, Smith contents that during the Roosevelt administration, shortly after the Cape Girardeau incident, rumors began to circulate in certain elite circles in Washington, and Roosevelt suddenly had an idea for a space program.

"The idea was to take a ship to the moon and bring it back safely," Smith says. "Not a rocket, but a spacecraft. Wherever did he get that idea?"

That tidbit of information, Smith says, was uncovered by British author Roald Dahl, who wrote "Willie Wonka and The Chocolate Factory."

Dahl, Smith says, was a spy for the British Security Coordination Unit, the goal of which was to get America involved in the war.

It was Dahl's association with friends with high ranking officials in the Roosevelt administration.

According to Smith, in July 1969, after the Apollo 11's landing on the moon, Dahl got a call from one of his old war buddies in Washington, and the two began reminiscing about a file that they had reported to the British intelligence service in the early '40s.

The file, the old friends remembered, contained information about Roosevelt's idea to send a craft to the moon.

As to what happened to the mystery UFO, Smith says it was purported recovered by the U.S. Army and taken to a military training facility in Sikeston, Missouri.

"There was a young man there; his name was Ben Schade -- his brother was Ruben Schade, and was the sheriff of Cape Girardeau County -- at one time he worked for the Southeast Missourian shortly after the crash incident," Smith says.

The book will cost $17.99 and will be available at Barnes and Noble, on Amazon.com and at other major booksellers.

Keep up with Smith's book at www.facebook.com/www.MO41BombshellBeforeRoswell/timeline