Either that, or there's a big time travelling twist that would take the show into a whole new dimension.
So what is this mysterious apparent error? Well, fans have noticed in the season 25 episode 'White Christmas Blues' that there are not one but two Moes. Oh dear god no.
In the scene in question, Mayor Quimby gathers Spingfieldians together to declare the town a tourist attraction, before Moe says in front of the crowd: "We will welcome the tourists with open arms – and then we'll gouge the hell out of them."
However, eagle-eyed fans on Reddit have spotted Moe in the crowd in the same shot – but noted that it was probably a mistake due to human error.
Yet others have their own theories, musing that it may be a time travelling Moe, one saying: "[Creator] Matt Groening is setting us up for the most epic time travel episode ever!"
Another joked that "they might be making [an] episode in the future where Moe travels back in time".
Perhaps he is The Moe-ster from Gallifrey? (Sorry).
In other Simpsons news, it was recently confirmed that Apu would no longer be voice by Hank Azaria following a documentary that presented the case that the character was racially problematic.
The Simpsons airs on FOX in the US, and on Sky One in the UK.
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