Most of us could probably recite episodes of ‘Friends’ word for word, but one keen-eyed fan has made a startling discovery while revisiting the classic sitcom on Netflix recently. In the season nine episode titled ‘The One With The Mugging’ there’s a split second where Rachel Green is NOT played by Jennifer Aniston and the internet’s mind is blown.

Jennifer AnistonJennifer Aniston played Rachel Green on ‘Friends’ (most of the time).

During one scene in the episode, Joey is enthusiastically ranting about the potential of a monkey also being at his audition, while Rachel stands behind him in a printed shirt. But when the camera pans back that’s not Jennifer Aniston standing behind Matt LeBlanc and she’s not even wearing the same shirt.

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Explaining the continuity error on Recently Heard, ‘Friends’ superfan Jordan D’Amico wrote, ‘Only a few minutes into the episode, an enthusiastic Rachel rushes into Monica’s apartment to tell Joey that he got an audition with the famous and fictional actor, Leonard Hayes, played by Jeff Goldblum.’

‘The three friends admit to admiring the actor for his cellphone commercials in which he starred opposite a monkey. Monica zealously posits that perhaps the monkey will be at the audition. Joey reacts by saying, “Don’t make me more nervous than I already am!” and goes to sit back down.’

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‘It’s at this point that… BAM! Who the hell are you and what did you do with our beloved Rachel?’ But it’s not the first time the show has been caught using a stand-in, other fans have also pointed out that a ‘fake Monica’ appears during a scene in Central Perk, from the show’s eighth series. Looks like it’s time for a massive ‘Friends’ binge to see what else we can spot.