It's been years since the photo of that white and gold dress (or is it blue and black?) split internet users 50-50, causing fierce debate throughout the world about its true colours.
The internet has continued to love a good optical illusion in the time since, with countless revisions of the original post being shared across the web.
While many of those weren't that impressive, there are still a few floating around that are genuinely mind-blowing - and the below is one of those.
Apparently, if you stare hard enough at one point on this image, all the colours disappear. That's right - it will go completely blank.
While the image has just gone viral thanks to it being posted on social media site Reddit, the optical illusion has actually been around for a long time.
This particular one was founded by Swiss doctor Ignaz Paul Vital Troxler in 1804, and is known as Troxler's fading.