We're connoisseurs of optical illusions around here—you never know when the next The Dress will hit the internet. (Hopefully it won't be as lame as that). This new one might not be quite as huge, but it's an awesome illusion. It occurred by complete accident in a photo of some young people taken in a U.K. nightclub. When 18-year-old Eleanor Bailey of Leeds looked at the pic, she noticed that her sister's arm looked like Mr. Fantastic. She was so amused, she had to upload it to Twitter, where it's gone viral.
We looked at this for a few minutes, but couldn't figure it out. Was a mirror involved? Is this some bizarre new Snapchat filter? Does she ACTUALLY HAVE SUPERPOWERS?
Sorry, we couldn't find a GIF of Mr. Fantastic.
The actual answer is pretty convoluted. No matter how much your brain is telling you otherwise, you have to understand that you're not seeing her right arm at all. She has it tucked behind her. The arm you're seeing belongs to the girl to her right, but the black of that girl's shirt and the guy's shirt makes it seem like the arm extends all the way around to Eleanor's sister.
Like all optical illusions, there's no magic to it. It's just an example of your brain failing at one of its most basic tasks. Let this be a reminder that you can never trust your own eyes. Sorry.