It is possible that the sensation of being followed is not just in your head.
An ethereal shadow figure is seen tailing the cameraperson in a viral video. There is a faint rainbow halo around the figure, which looks more like a 1950s sci-fi film than a camera phone.
Chris Randall wrote in his post that he wanted to see it out of the corner of his eye.
Randall said that he had experienced his first Brocken Spectre, a mind-bending optical illusion that occurs on misty days when the Sun casts a shadow of a person on the fog, causing the shadow to be both magnified and take on.
They were named after the German mountain range where they were first described by a scientist in the 18th century. From Scotland's Big Grey Man to the Buddha's Light in China, there's a lot of mythology surrounding these ghosts.
These specters are easy to create while hiking and have become a meme in the social media era.
This unmanufactured and very scary Brocken spectre is all the more poignant because it was posted on a site that could soon become a ghost.
There are more things to think about. The optical illusion makes you feel like you're falling down.