It may be Monday morning, but that hasn't stopped the internet from deciding to give our brains a workout.
A photo that seems innocent enough is sending people into a spin as not all is what it seems.
The snap — which features a group of schoolgirls posing with a tortoise — is doing the rounds online as people realise what they're seeing isn't what they expect.
Take a look for yourself.
If you see the girls all clad in different coloured T-shirts, including blue, yellow, red and green, then you're not alone.
But you may be shocked discover the photo is actually black and white.
If that's blown your mind, allow us to explain.
The photo, which has been retweeted 12,500 times, is lined with colours, which sprawl across it in a grid manner, allowing your brain to "predict" the reality of the photo.
Essentially, you filling the blanks in your mind, according to Twitter user Lionel Page who shared the brainteaser.
On Reddit, where the mind-boggling optical illusion was shared initially, people have been stunned by the reality of the snap.
For me, the green and blue lines work the best and seamlessly blend into the background.
"Red looks like a grid on a grey background," one person said.
Another said: "I think it's because the contrast between the red and dark coloured shirt is greater than that of any other colour combination in the picture.
"I know the human eye can see more shades of green than any other colour, but I'd imagine we see red more quickly because it implies danger (same colour as blood)."
"Only the shirts appear to have colour, the skin looks grey," another person wrote.
OPTICAL ILLUSIONS THAT DROVE US CRAZY
This isn't the first optical illusion to sweep the internet this month, with a headache inducing viral snap creating a huge divide recently.
The snap left some people seeing a stunning beach shore, as others made out something a lot more mundane.
So what do you see?
According to the Twitter user Nayem, if you see a "beach, ocean sky, rocks and stars" then you're clearly a creative person, such as an artist.
The reality is the image is a snap of a broken car door that needs to be repaired, pronto. In order to see this, it apparently helps if you flip it on its side.
Bizarrely, it's not the first time people have debated over whether an image is a beach or a car door. Last year, an image of a stunning beach went viral as people struggled to decipher whether it really was a beach — or a very exciting door.
That time, though, it really was a beach.
On the subject of cars, an aerial image of a geometrical car park in the UK baffled the internet back in February.
Shared by a British photographer on Instagram captioned, "Counting cars" the innocent post from Abstract Aerial Art sparked a frenzy as followers desperately try to figure out how many vacant spots there were among the parked cars.
A user posted the image to Reddit where they shared the optical illusion, asking users: "How many spaces do YOU see?"
"Only genuises get it right, 99% of people get it wrong," the user added.
How many cars there actually are still remains unclear.