It's an X-rated version of #thedress.
At first glance, it may seem as if these British children's TV entertainers have been photo-bombed by a gigantic penis.
The enormous member appears to be rising out of a glass held by fan Jemima Campion, who's alongside the Chuckle Brothers -- Barry and Paul -- in the snap.
But thankfully, it's just an amazing optical illusion -- a trick of the light converting her arm into something much more adult-oriented.
The image of the comedy duo -- who hosted their own children's slapstick-style show on British TV for several decades -- alongside 19-year-old Campion was taken at the Pryzm nightclub in Leeds earlier this month.
It was posted to Twitter by Solita NQ restaurant in Manchester on Wednesday, and soon went viral, sparking a host of these joke replies:
College student Campion told the Mirror that the optical illusion was "completely unintentional."
"I didn't intend to put my arm or my hair in that position at all. The pink bit you can see on my shoulder is not my bra strap but the lighting," she told the publication.
Initially, she was "mortified" when the image started going viral, but has since learned to take it as a joke. She's also vowed to be more careful when posing with celebrities in future.
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