Footage from 1938 unearthed online has offered ‘proof’ that time travel is real, according to some commentators.
In the film clip of people walking towards the camera, one young woman can be seen holding something to the side of her head.
Conspiracy theorists claimed the woman has been caught on film chatting on a mobile phone, decades before the technology was invented.
The woman can be seen chatting as she walks in the crowd of people, with the device clamped to the side of her head with one hand. She then lowers it before the film clip ends.
As the woman, clad in a stylish 30s dress, lowers the object from her ea,r it can be seen as a dark hand-sized item; the same dimensions as a modern mobile phone.
The mystery deepens when one YouTuber came forward claiming the woman in the shot was their great-grandmother, and she was in fact using a mobile phone.
According to YouTube user Planetcheck, the divide is an experimental wireless phone developed by industrial giant Dupont at their factory in Leominster, Massachusetts.
“The lady you see is my great-grandmother Gertrude Jones,” the user said.
“She was 17 years old. I asked her about this video and she remembers it quite clearly. She says Dupont had a telephone communications section in the factory.
“They were experimenting with wireless telephones. Gertrude and five other women were given these wireless phones to test out for a week.
“Gertrude is talking to one of the scientists holding another wireless phone who is off to her right as she walks by.”
It comes after bizarre claims that a picture from 350 years ago also contains a mobile phone.
The picture, the work of Dutch painter Pieter de Hooch showing a quaint domestic scene, is so convincing even Apple's CEO seemingly thinks it shows an iPhone.
The supposed image of an iPhone - centuries before the devices were first created - can be seen in the hands of a man standing to the right of the picture according to conspiracy theorists. He is holding a small object, while a couple of women and dogs look on.
Meanwhile archaeology fans cedlaim they finally have "proof" of time travel, after a helicopter and plane were found on ancient Egyptian hieroglyphs.
The 3,000-year-old sacred carvings were discovered in Seti I's temple in Abydos, one of the oldest cities in the historic country.
Archaeology enthusiasts suggest the precious inscriptions appear to show a futuristic-looking aircraft among snakes and insects.
Pseudoscientists claim a photo of what is now known as the Helicopter Hieroglyphs is proof that time travel actually exists.