The origin of the Mind Flayer has been on the minds of Stranger Things fans for a while, and we think it could be 001, the original experiment of the Hawkins National Laboratory. For the entirety of the Netflix original sci-fi series, Eleven (Millie Bobby Brown) has been the central protagonist. After dealing with threats from the Upside Down and closing the Gate, she then became the target of the dimension's ruler, the Mind Flayer, in season 3.

The Mind Flayer possessed Will Byers during season 2 but found Billy Hargrove to be its new host in season 3. Even though it became clear that one of the main goals of the Mind Flayer was to kill Eleven, Stranger Things hasn't revealed much else about the powerful creature. How and when it was created is one of Stranger Things' biggest unanswered questions, and has left many viewers searching for answers. The same could be said about the introduction of other test subjects during season 2, which made us wonder if the Mind Flayer could be the very first one.

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As discussed in Screen Rant's latest video, we think that the Mind Flayer could be test subject 001 in Stranger Things. This theory is based around the power that it possesses, ties to Hawkins Lab, and its interest in Eleven, but also a general lack of knowledge on its past. Plus, it could help the show come full circle with its story in a potential fourth season and tie up some currently loose threads from season 2. Check out the video at the top of this post for the full theory.

The introduction of 008 in season 2 was one of Stranger Things' most divisive decisions, as it resulted in a bottle episode of Eleven with Kali Prasad aka Eight (Linnea Berthelsen) and her group of runaways. Season 3 had no appearance from Eight or that of another powered person, but since Eight and Eleven are the only ones that Stranger Things has introduced, that means there are at least nine other individuals with different powersets who could exist in this world.

The Mind Flayer could be 001 and have been trapped in the Upside Down for several years or created the entire dimension itself. It's even possible that the reason Hawkins Lab began experimenting on other children was to find a potential equal to the Mind Flayer, which Eleven clearly is. This reveal could then push Eleven to find a way to regain her abilities so that she could defeat the Mind Flayer and any additional threats from the Upside Down for good.

This is just a theory at the moment, so it will be up to Stranger Things season 4 to prove this to be true. As of right now, Netflix has yet to renew the series for another season officially, but that announcement is heavily expected to be on the way. Even once the next season is announced, there is no guarantee that the Mind Flayer and its origin will be something that Stranger Things explores. If it does, then this is a compelling theory as to what could be in the Mind Flayer's past and Stranger Things' future.

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