What’s that, you thought Thomas Edison invented the Motion Picture Camera? Au contraire my friend - Louis Le Prince applied for a patent on his camera well before Edison, but was denied due to an interfering patent. Edison, who later applied, was granted his patent with no opposition.
Louis Le Prince, who later became a US citizen, continued to research and develop his camera. In September of 1890, his plan to perform a public exhibition of his camera at Jumel Mansion, New York was cut short due to his disappearance.
In September 1890, Le Prince boarded a train on a Friday, promising friends he would rejoin them in Paris on the following Monday for the return journey to England, to be followed by a trip to the US to promote his new camera. However, Le Prince did not arrive at the appointed time and he was never seen again by his family or friends. All that could be established about his last whereabouts was that he was seen on 16 September 1890 boarding the 2:42 train at Dijon for his return to Paris.
The French police, Scotland Yard and the family undertook exhaustive searches but never found his body or luggage. This mysterious disappearance case was never solved.
Many theories have been suggested, varying from suicide to an elaborately planned self-disappearing act ordered by his family. All these theories could be plausible, but my favorite theory deploys much more sinister implications.
Patent Wars assassination, "Equity 6928" (1900):
Christopher Rawlence pursues the assassination theory, along with other theories, and discusses the Le Prince family's suspicions of Thomas Edison over patents (the Equity 6928) in his 1990 book and documentary The Missing Reel. At the time that he vanished, Le Prince was about to patent his 1889 projector in England and then leave Europe for his scheduled New York official exhibition. His widow assumed foul play though no concrete evidence has ever emerged and Rawlence prefers the suicide theory. In 1898, Le Prince's elder son Adolphe, who had assisted his father in many of his experiments, was called as a witness for the American Mutoscope Company in their litigation with Edison [Equity 6928]. By citing Le Prince's achievements Mutuscope hoped to annul Edison's subsequent claims to have invented the moving picture camera. Le Prince's widow Lizzie and Adolphe hoped that this would gain recognition for Le Prince's achievement but when the case went against Mutoscope their hopes were dashed. Two years later Adolphe Le Prince was found dead while out duck shooting on Fire Island near New York. Suicide was presumed.
Like any good conspiracy, this theory can in no way be proved. Although many would argue that Edison was a mean old bastard capable of ordering the assassination, there is no hard-core evidence to prove his evolvement.
In 2003, while doing research in the Paris Police Archives, the photo of a drowning victim was found – believed to be Louis Le Prince.
Le Prince had indeed succeeded making pictures move at least seven years before the Lumière brothers and Thomas Edison, and so suggests a re-writing of the history of early cinema." Richard Howells (Screen vol.47 #2, p.179~200, Oxford University Press, 2006