Can you work out what's REALLY going on in this optical illusion that is baffling the Internet?

Can you spot what's going on here?! [Imgur]Can you work out what's REALLY going on in this optical illusion that is baffling the Internet? You might do a double-take at this mind-boggling image! This photo of three friends is baffling the Internet - and for good reason. At first glance, to look at the photo of three young friends smiling happily you wouldn't notice anything weird. It becomes clear on closer inspection  [Imgur]The celebrating ...