An eagle-eyed Friends fan has made a shocking discovery - there was a moment where Rachel wasn't played by Jennifer Aniston.
The random recasting occurred in season 9 episode 15, 'The One with the Mugging', where a stand-in is spotted for a couple of seconds.
The woman doesn't look at all like the actress and is wearing a completely different top as she stands grinning behind Joey.
So how has no-one noticed it before? Now it's been pointed out, it's really, really obvious...
Well, don't be too stunned - there is a fairly simple explanation. The moment comes from the HD remastered version of the episode, which has a 16:9 aspect ratio - wider than the 4:3 format it was originally edited to be broadcast in.
In other words, none of us would have been able to see the Anti-Rachel when the show went out on TV, as the sides of the screen would have been cut off, and it's only in its polished, widescreen format that the stand-in reveals herself.
It's not the first time it's happened on a HD remaster of a classic show. Indeed, it isn't even the first time it's happened on Friends, as fake Monica will have you know:
Which begs the question - how many other times did this happen on the New York sitcom? And if that's not an excuse to binge-watch the entire series all over again, we don't know what is...
Tasha is a freelance writer for with a particular interest in the representation of women in film and TV. After graduating with a Literature degree then journalism qualifications with News Associates a few years further back than she’d like to admit, Tasha began her freelance career. She’s worked as a writer, editor and commissioning editor for a number of publications including Digital Spy. She is also a theatre critic. LinkedIn