I picked an odd time to start replaying Mass Effect 3.

I’ve been revisiting Bioware’s beloved sci-fi shooter series over the last month and a half, trudging my way through stopping Saren in the original game and recruiting an elite team for the suicide mission in Mass Effect 2, but my playthrough of the trilogy saw me kickstart Mass Effect 3 on Christmas, right as Netflix was dropping the second volume of Stranger Things‘ fifth and final season. A few weeks later, I’m knee-deep in trying to stop the Quarians and Geth from killing each other over their homeworld, and Stranger Things fans, in the wake of a controversial series finale dropping over New Years, have found themselves wrapped up in layers of post-release aftermath interviews and a fervent belief that actually, if you follow the right clues, a secret ninth and final “true ending” episode is imminent.

Rather was, and now might still be. Even though I am not a big Stranger Things follower personally, cries of “Conformity Gate”—and now “Documentary Theory” ahead of next week’s release of One Last Adventure, a behind-the-scenes breakdown of filming the final season that some have started to believe is a metatextual show-within-a-show—have been inescapable this week. Anticipation for a theorized release date for this secret last episode came and went, sparking further waves of consternation as true believers—and social media grifters yearning to keep the attention cycle going—proclaimed that there was still a chance, that Netflix’s claims to the contrary were not to the contrary at all, and that you just have to divine the right flavor of fandom zealotry out of a number in a picture here or a word in an Instagram comment there.

The fervor has attracted plenty of attention, wondering just how and why these kinds of delusions begin in the first place. Was it Stranger Things‘ fault, having spent the best part of a decade training its devoted audience to look for clues anywhere, or was there some other pop cultural root cause we can blame? After all, Stranger Things is far from the first series to come to a broadly unsatisfactory end for its viewers. It is likewise not the first to end in such a way, with such a dedicated fanbase, to inspire belief that the ending couldn’t be bad on purpose, its weaknesses so obvious that it must be a sign of a “real” ending to come that would make up for it all.

© Netflix

Some commentators have turned to BBC’s Sherlock, which wrapped up in 2017 so messily that it sparked a similar wave of belief, inspired by the show’s predilection for mysteries and clues, that a new episode would be on the way. Others have turned to the release of Justice League that same year, a famously compromised production that saw original director Zack Snyder depart the project and Joss Whedon attempt to pick up the pieces to horrendous effect—although in that case, the campaign for what would eventually become known as the “Snyder Cut” would be sparked not solely by fandom theorization, but by Snyder himself spending years insinuating its existence (four years, millions of dollars, and a desperate need for exclusive programming on Warner Bros’ new streaming service later, they got their wish).

But I didn’t just randomly mention the Mass Effect series in my introduction—if you go just five years prior to either of those inflection points back to the release of Mass Effect 3, you’ll see a lot more parallels to the situation with Stranger Things we have today.

When the climax of Bioware’s RPG trilogy was released in 2012, it famously did so with an ending that quickly became a source of fiercely debated scorn. Awkward narrative steps in the game’s final act—which sees you and the intergalactic army you’d spent the rest of Mass Effect 3 recruiting assault Earth itself in an attempt to liberate it from, and ultimately defeat, the synthetic apocalyptic threat of the sinister Reapers—and an ending to a choice-and-consequence-driven series that by and large funnelled you to one of three spins on a broadly similar conclusion saw fans almost immediately start mocking and hoping in equal measure that this was not what five years and a hundred-plus hours of gameplay across three games had actually built to.

Teeth were gnashed, cupcakes were delivered to Bioware—at the time a divisively petty move that now somehow comes across as charmingly quaint after the almost decade and a half of increasingly hostile fandom movements that have come since—but something began to cut through the noise: the Indoctrination Theory.

© Bioware

Named for the method of insidious mind control the Reapers were capable of using to enthrall swaths of agents and galactic populations to ensure their harvesting of organic life could happen with as little resistance as possible, the Indoctrination Theory posited that Mass Effect‘s hero, Commander Shepard, had slowly but surely become a victim of indoctrination himself since he first encountered the Reaper Sovereign in the original game. Climaxing with the completion of the indoctrination in Mass Effect 3‘s final battle, the theory argued that the supposed lack of clarity and plot holes of the game’s ending sequences, as well as the color-coded final choice not aligning with the series’ preferred color palette for “Paragon” (altruistic, collectivist) or “Renegade” (aggressive, independent) moralities, was an indication that the Reapers were lulling Shepard into a hallucinated state, stopping the commander from making the choice to destroy them once and for all.

Once the Indoctrination Theory first hit, it spread like wildfire, as fans looked back across the entire trilogy to find supporting evidence and looked to it as definitive proof that Bioware was planning to sell fans a “true” ending, coalescing all of the frustrations and indignation people felt behind this body of purported proof. Bioware stayed silent until three months after release, when the developer announced the “Extended Cut,” a free-to-download expansion for the game that added new cutscenes and altered others in Mass Effect 3‘s climax, as well as providing a new epilogue, to both address some of the lack of clarity in the original sequences and provide a chance to put aside months of debate and lay out what the developers’ original intention for the ending to the series actually was.

A year later, after the brunt of the controversy surrounding the endings had been blunted by both the Extended Cut and the passage of time, Bioware sunset its support of Mass Effect 3 with a separate paid DLC called Citadel, a less-maudlin and jovial sendoff to Mass Effect‘s cast of characters that let players celebrate with their favorite party members one last time. But even if that controversy flamed out (and the Indoctrination Theory still has its proponents, even after Bioware dismissed it years later as never being an intended reading of the series), its impact is still being felt to this day.

© Bioware

In some ways, part of the reason we still see situations like the one with Stranger Things is that—whether it saw it as such or otherwise—Bioware gave Mass Effect fans what they wanted, willing into existence things that weren’t originally planned, even if it wasn’t the form those initial fan theories presumed it would be. It helped lay the groundwork that, with enough speculation and enough pressure by audiences, a disagreeable finale could be made somewhat more palatable, even if not wholly redone. While in the end it may have turned out better for the Mass Effect saga—even if, by and large, we’re still really waiting to see the future of the series beyond Mass Effect 3‘s ending—whether it’s turned out better for a fandom’s relationship with the people who created the works they adore is still, as this week shows, a work in progress.

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