Beach pic goes viral - can you spot why?

These six girls are posing for that holiday snap on the sand, but everything is not what it seems…

Can you see what made this photo go viral?

Plenty of Instagram users were stumped by the challenge and it has nothing to do with their brightly-coloured bikinis.

“It took me 9 hours to figure out,” admitted one.

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We will give you a hint, it has something to do with the guy in shades who appears to be photobombing the happy snap.

Yep - spoiler alert - one social media prankster has performed a faceswap on all six ladies.

They share the same open-mouthed expression and all appear to be wearing the same sunnies too.

This isn’t the first ‘optical illusion’ to stump the Interwebs and we are sure it won’t be the last…

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