"The One Where They Leave In Rachel's Stand-In" might not be an actual episode, but it did happen. Twice.

Almost 20 years after the show went off air, the beloved sitcom has once again gone viral after fans . In season 9, episode 15 of the show titled "The One With The Mugging," there is a scene where the camera pans to Joey, played by , with what is supposed to be 's Rachel standing in the background.

Except it's not Jennifer Aniston. —and half of her face just visible past Joey.

And on top of that, it turns out this isn't the only time during the same season.

In the fourth episode of season nine, "The One With The Sharks," Jennifer's stand-in once again makes it into the final cut. Caught by a fan and then shared to Twitter, approximately 12 and a half minutes into the episode, a curly-haired Rachel can be seen at the kitchen table wearing a yellow shirt.

When the camera shifts to the table again, Jennifer's straight-haired stand-in has taken her place wearing a blue shirt.

Mistakes aside, Friends' popularity has endured since it ended nearly 20 years ago.

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