The following is a lightly edited excerpt from the latest Decoder Ring podcast. Listen to the full episode using the audio player below, or via Apple Podcasts, Overcast, Spotify, Stitcher, or Google Play.

Scores of TV shows, movies, and books inspire fan fervor, but none have done so for as long as Sherlock Holmes. The character, created by Arthur Conan Doyle, first appeared in 1887 in the novel A Study in Scarlet. In addition to the 56 original short stories and four original novels, Holmes has appeared in tens of thousands of books, plays, movies, musicals, radio shows, TV shows, cartoons, comics, and board games all over the world. He’s been an animated mouse and a drug addict. He’s solved crimes in the 22nd century and been suspected of being Jack the Ripper. Currently, he’s played by Robert Downey Jr. in a movie franchise, solves crimes with a female Watson on CBS’s Elementary, and is an odd charismatic genius who texts a lot in the BBC’s Sherlock.

That show, created by Steven Moffat and Mark Gatiss, began airing in 2010. Set in modern London, it’s sharp and sophisticated. There are four three-episode seasons and one holiday special, with most of the episodes riffing on one of the original Conan Doyle stories. Sherlock Holmes has always been aloof, cold, smarter, and more logical than the rest of us, but Sherlock accentuated the character’s social awkwardness. Sherlock describes himself as a sociopath. Then Holmes meets John Watson, portrayed by Martin Freeman, an army doctor and Afghanistan war vet overcoming PTSD. They become roommates, living together at 221b Baker St. as friends, confidants, and partners.

Sherlock was a hit immediately upon its release in the U.K., popular and well-reviewed. A passionate fandom sprung up around the show on fan-fic sites and social media platforms like Tumblr. On AO3, one of the main sites for publishing fan fiction, there are currently more than 116,000 stories about Sherlock Holmes, and about half of those are about Sherlock and Watson. Between 2011 and 2016, nearly 300 Sherlock fan works were being published every week. The show’s fans were—and still are—mostly women, many of whom were queer and not necessarily interested in how faithful Sherlock was to the original Sherlock Holmes stories. They analyzed the show, riffed on it, chatted about it, built a community around it, and they rooted for various romantic relationships—known as ships—but most especially, they rooted for Johnlock, the nickname for the romance between Watson and Holmes.

Many of the most popular ships, the majority even, are slash: That’s the term to describes gay-male pairings. The term slash, like so much about modern fandom, comes from Star Trek fans, who starting in the 1970s would use a slash in the title of a zine—Kirk/Spock—to tip readers off to its sexual content. Since Kirk and Spock, there have been thousands of slash ships shipped. But there’s only one that is longer-lived: Sherlock Holmes and John Watson.

And the thing about Holmes and Watson, like Spock and Kirk—who are, in their way, modeled on Holmes and Watson—is that the idea that something romantic might be going on between them is not new. Conan Doyle wasn’t trying to create a homosexual subtext when he wrote the characters, but he did write a deep and committed friendship, and Johnlock shippers are not the first people to see something romantic in that bond, not the first people, to put it in academic terminology, who have “queered the text.”

In 1941, the mystery writer Rex Stout wrote a piece of Sherlockian analysis called “Watson Was a Woman,” in which he did a close reading of the stories and concluded that Watson must be Sherlock’s wife. In the 1970 Billy Wilder film The Private Life of Sherlock Holmes, a favorite of Sherlock co-creator Mark Gatiss (an openly gay man himself), it’s strongly implied that Sherlock Holmes is gay.

The BBC Sherlock knew about this history and winked at it. In the first 15 minutes of the first episode, Holmes and Watson’s landlady asks if they’ll be sharing a bed. And that was only the start. But according to the people making and starring in the show, all this is just subtext. Sherlock Holmes and John Watson are platonic. Many fans disagreed.

This discrepancy between what the people making the show and the people watching the show think could happen on the show is normal. This gap—between what the creators put on screen and the ways fans interpret it and expand on it and argue with it—that’s the elemental stuff of fandom, the space fandom needs to exist. Fans sometimes come up with dynamics and events and conversations and interpretations and, yes, sexual arrangements, that no show ever would or could. And most of the time, this isn’t just fine, it’s the fun.

But then in 2014, just after Season 3 of the show aired, a user posted a very elaborate fan theory online. When I say very elaborate, I mean it was tens of thousands of words of high-minded literary analysis that began by interpreting a BBC report on queer representation and then went on to closely read every episode of Sherlock, the shot composition, the score, the colors, the lighting, the dialogue, the references, the letters in the character’s names, all with a helping of string theory.

The idea all this analysis led to was that John Watson and Sherlock Holmes were not only characters with gay subtext who should be together, they were gay characters who were going to get together in the show. Johnlock was going to happen, for real, most likely in the then-upcoming Season 4.

This became known as the Johnlock conspiracy: TJLC for short. Much of the theory is based on close textual analysis, the kind an English teacher would love. But TJLC wasn’t based only on close readings of the show. You have to understand, Sherlock and John could only be getting together if the creators were lying to viewers—because the creators said, over and over, no way, it’s not going to happen. Now, to be fair, the creators did often lie. Steven Moffat, who was also the showrunner for Doctor Who, is especially well-known for misleading fans and the press about specific plot points in the shows he makes, both in interviews and at panels at fan conventions. But when it came to questions about Johnlock as a romantic pairing, the showrunners became particularly unequivocal.

In July 2016, before the fourth season aired but after TJLC was a widespread theory in the community, Mark Gatiss said at a fan convention: “We’ve explicitly said this is not going to happen. There is no game plan, no matter how much we lie about other things, that this show is going to culminate in Martin and Benedict going off into the sunset together. … We’re not trying to fuck with people’s heads. Not trying to insult anybody or make any kind of issue out of it. There’s nothing there.”

But some fans remained convinced these denials were just a diversion. In the second part of an exhaustive 48-part YouTube series called TJLC Explained, the host declares, “Almost every time the writers or actors come out or say something, I see people being discouraged and worrying Johnlock won’t happen. … I hope this video can dispel some of your fears: TJLC is real.”

She’s standing in front of a color-coordinated bookcase, grinning throughout. You can see, and hear, the peppy excitement she feels just talking about this idea: “Ultimately, it doesn’t matter what they say. … This is the closest to being a genuine conspiracy that TJLC actually gets, because you have to believe that everyone involved is hiding the truth. It’s not a stretch to believe it, though, because the writers have told us time and again that they’re doing it.”

Whether or not Moffat and Gatiss are lying is one of the fundamental question of TJLC. And it’s one we can’t really know the answer to. It’s not possible to prove that someone is lying about something that hasn’t happened yet—until it doesn’t happen, which we won’t know until Sherlock is over forever. And as long as there is potentially more Sherlock, it always could. TJLC became, for some people, irrefutable.

I want to be clear that there were people who were into Johnlock or TJLC in different ways, who thought of it primarily as a great hope or a fun idea or a worthy cause, a huge leap forward for gay representation. But for some TJLCers it became an eventuality, not an opinion or a possibility. Shipping other pairs or doubting the theory, even thinking it was really clever but probably not going to happen, was denying that truth, not just one ship among many. For some fans, TJLC became too important to doubt—so they started to attack the doubters, who then attacked back.

To learn more about TJLC and how the Sherlock fandom divided, listen to Episode 2 of Decoder Ring.