The Missouri ‘Madman’ Who Built a Time Machine then Disappeared
Many have tried to build a time machine and no one (that we know of) has been successful. The one exception might be a Missouri guy who was called a "madman" when he claimed he built a contraption to travel through time. The strange aspect of his story is that he eventually really did disappear.
His name is "Madman" Mike Marcum. Unlike some urban legends, it's possible to prove Mike existed. There's a Wikipedia page dedicated to Mike's story. On September 4 of 1995, Mike Marcum appeared on the nationally-syndicated Art Bell radio show. His claim was extraordinary. He said he had figured out a formula to build a time machine complete with schematics. Mysteries Unsolved even shared a picture of the diagram they claim that Mike created.
Mike Marcum wanted to create what he called a "Jacob's Ladder". What he actually came up with was allegedly much more.
Now is where the story gets extremely weird. "Madman" Mike Marcum's appearance on Art Bell inspired hundreds to try and contact him by 1997. Some even traveled to Mike's home in Missouri. One big problem. "Madman" Mike Marcum had disappeared.
But, wait. The mystery deepens.
On the Missouri sub-Reddit, there was a report that an unidentified man who resembled "Madman" Mike Marcum had been found deceased...in the 1930's.
To state the obvious, it cannot be proven that "Madman" Mike Marcum traveled through time and died on a beach in California in the 1930's. However, I am not aware of anyone else that claims to have created a time machine that really did disappear in unusual circumstances.
To this day, the mystery of where "Madman" Mike Marcum went is unsolved.