Nothing gets past EastEnders fans...
But it wasn't the iconic storyline that got them talking, or seeing some of Walford's most familiar faces back on their screens.
No, it was Kathy Beale's amazing ability to freeze time.
The now-infamous scenes of 'Sharongate' saw Grant Mitchell discover wife Sharon (Letitia Dean) has been sleeping with his brother, Phil (Steve McFadden) behind his back... and, of course, all hell broke loose.
The shocking revelation happened in the middle of the Queen Vic pub, and to make matters worse the place was packed with locals for Phil and Kathy's engagement party.
The truth is revealed...
Kathy was stunned to find out her husband-to-be had been sleeping with Sharon... but despite the fact her engagement party was ruined, she still managed to look amazing.
Fans couldn't help but notice that Kathy hasn't aged a day since this episode was filmed in 1994.
It might be more than 25 years since the episode aired, but actress Gillian Taylforth, who plays legendary Kathy, still looks the same as she did more than 25 years ago.
Fans took to social media to share their shock...
The episode also saw Walford favourites returning to the screen like Pauline and Arthur Fowler, along with Sharon's best friend Michelle.
Nigel and Debbie Bates were also part of the drama, as were former couple Carol and Alan Jackson.
Next week will see Syed and Amira's iconic wedding from 2010 air as part of the soap's ongoing classic episodes that will air every Tuesday.
BBC1 will air EastEnders: Secrets from the Square, hosted by Stacey Dooley, at 8pm on Mondays, while classic episodes of the soap will air at 7.30pm on Tuesdays.
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