On Monday, Instagram user Hunter Culverhouse shared this mind-bending photo of their legs to their Instagram account.
People were instantly confused by the photo (which had been taken down by Wednesday afternoon).
Why are these legs so shiny?
Spoiler alert: It's not oil, it's white marks.
The picture was picked up by Twitter accounts, who helped spread the hysteria.
Some people were confused.
Then also kinda mad that the illusion had been spoiled for them.
Maybe keep this one a secret if you know...
Culverhouse said the whole thing was sort of an accident.
"I was finishing off some art homework and had some white paint left on my brush and just decided to draw random lines, I had no intentions of making it look shiny," Culverhouse told BuzzFeed News.