WARNING: The following article contains spoilers for Season 3, Episode 57 of Attack On Titan, "That Day."

With Attack On Titan fans still coming to grips with the truth bomb dropped by "The Basement," along comes "That Day," which not only expands on the previous episode's revelation but also blows human/Titan history wide open. And, as manga readers already know, it's highly divisive.

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The latest episode of Season 3 picks up where the last one left off, in Grisha Jaeger's past. We experience it entirely as a flashback, playing out in the form of a lucid dream in Eren's head, and narrated by an adult Grisha, presumably from the journal entries his son discovered in their family basement. From a geography lesson that Grisha's dad gives him, we learn that Grisha's original home is part of a larger continent, while Eren's is a smaller, island colony, called "Paradis Island."

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Grandfather Jaeger also imparts some censored history on his wide-eyed son: "1,820 years ago, our ancestor, Ymir Fritz, made a contract with the Earth Devil for power. The power of the Titans." From Ymir, the first Titan, the Eldian race was born, uniquely gifted with the latent genetic ability to become Titans. Following Ymir's death, her soul was split into nine Titans, each containing a different portion of her powers. The Eldians harnessed that to create a "great and ancient nation." Unfortunately, this nation's "greatness" was built on the back of oppressing those deemed inferior.

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The Eldian Empire ushered in a "Dark Age," but their global rule was impeded by a festering distrust between their ruling Titan monarchs. The "Great Titan War," broke out, bringing the Empire to its knees. Seven of the nine Titans were lost to the nation of Marley. That was how Paradis Island came to be: It's the last remaining Eldian stronghold, walled off from the rest of the world by King Karl Fritz, who used the Founding Titan power to erase the burden of knowledge from his people's collective memory and embed a defensive line of Titans in the walls to repel any incoming human intruders.

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Eighty years, passed and any Eldians left in Marley, like the Jaeger family, ironically fell victim to a similar subjugation once dished out by their ancestors. We see Grisha and his sister, Fay, forced to wear armbands marking them out as lesser when they venture outside their home and, when they sneak into a different district, they are violently punished for their disobedience. Here, Fay meets a sticky end that her older brother doesn't learn the truth of until years later, spurring him to join an underground resistance movement, the Eldian "Restorationists."

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Using intelligence from a mole in Marleyan law enforcement known only as "The Owl," the Restorationsists plot to overthrow their abusive overlords, only to be discovered and sentenced to a creatively cruel punishment. The Marleyans turn the Eldian's gift against them -- lining up Grisha and the rest of the dissenters on top of the city's walls and forcibly injecting them with Titan spinal fluid. Sending one unturned Eldian loose as bait, the newly made Titans are released into the desert that lies outside.

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If any of those Titans look at all familiar, it's because they should. The implication here is that this is the source of the steady stream of Titans that have besieged Paradis Island for all of these years. Luckily for Grisha, the Owl reveals himself just before his "life sentence" can be doled out. The Eldian spy turns out to be the very officer who beat Grisha up as a child, and a shocked Grisha watches as his savior unleashes his Titan power -- which looks an awful lot like Eren's, shaggy-haired Titan form ...

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With this influx of new information about creator, Hajime Isayama's world (new to anime viewers only, at least), comes an uncomfortable analogy to digest. Many have interpreted the armband-wearing, oppressed Eldians as clear ciphers for Jewish people, which, following this analogy, makes their desire to control the world and their ability to transform into hideous, greedy monsters conform to some highly offensive stereotypes. However, there's also little denying that even with Eldia's problematic history, the Empire's modern-day descendants are largely portrayed as sympathetic heroes.

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Now that Eren and the rest of the inhabitants of Paradis Island are no longer in the dark about their people's past, what they choose to do with that information could prove crucial in untangling Isayama's intent with this controversial, real-world parallel, as well as setting the course for the show's future.

New episodes of Attack on Titan are available to stream on Crunchyroll and FUNimnation, and air every Saturday night as part of Adult Swim's Toonami block.