TikTok brainteaser is sending the internet into a frenzy. Can you spot the mistake?

A simple brain teaser sent the internet into a frenzy when it went viral on TikTok this week.

In the video, which has more than 3.5 million views, a man asked two women a seemingly simple question.

WATCH THE VIDEO ABOVE: Brain teaser goes viral.

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The man first unveils a piece of paper that reads, “Can you spot the ERROR?”

Below are the numbers 1, 2, 3, 4, 5, 6, 7, 8, 9 written in rainbow colors.

TikTok posted by House of Highlights shows the women reading the phrase over and over again.

At first the women wondered if the numbers were in the wrong order, but they appeared to be correct.

They then suggested that “error” might have been misspelled, but it was spelled correctly.

“Is it something to do with the colors?” one of them asked.

“Has it something to do with there being two greens? ‘Cause that’s red, orange, green, green?”

The women could not uncover the mistake.

“This will kill you when you find out,” the man laughed.

Eventually the women were even sure that there was nothing wrong – and that was the trick the man played on them.

The mistake was never revealed and the video ends with the two women growing increasingly frustrated.

As it turned out, the mistake was that the word “the” was spelled twice in the sentence.

Many social media users scratched their heads and admitted they went straight to the comments to find the answer.

“It took me longer than I’d like to admit, I’m tired,” said one.

“Let me go for a minute,” added another.

“It’s so funny how the brain automatically corrects things like that! I found it, but it definitely cost me a bit,” commented a third.