I gotta say, 2018 has been a very odd year to be an X-Files fan. On the one hand, we got a new season of the show complete with a brilliantly bonkers new Darin Morgan episode and confirmation that Mulder and Scully are totally doing it. But on the other hand, we got that really gross “impregnated by science” nonsense and a truly slapdash finale. Gillian Anderson announced she’s done with the show and, honestly, who can blame her? But let’s not focus on 2018, at least not for the next couple hundred words. Instead, let’s travel back to exactly 20 years ago today when X-Files hit what was arguably the height of its pop culture power, when it pulled of something that really no other TV show has done before or since. 20 years ago today, the X-Files feature film hit theaters and earned this cult franchise a spot in the pop culture pantheon.

X-Files: Fight the Future (as I’ve always called it–that was, after all, the name on the official soundtrack!) is different from every other movie based on a TV show. In fact, this kind of movie/TV synergy is the kinda thing you would expect to see today (but still don’t!). Basically, The X-Files did what Marvel is still trying to do. Fight the Future takes place in-between seasons 5 and 6 of The X-Files TV show. The movie continues from the Season 5 finale, and the Season 6 premiere picks up from where the movie ended. Like, the “previously on” recap for the Season 6 premiere includes footage from the movie!

Take a step back and think about that for a second. How many times has a TV show released a movie during the show’s initial run, and had that movie actually count as a chapter of canon? TV shows have reunion movies all the time (Firefly, Entourage, Absolutely Fabulous, Sex and the City), but those movies take place after the show has ended. And all the times a show has released a movie while it’s still on air, the movie was usually ignored. Batman: Mask of the Phantasm didn’t have an impact on Batman: The Animated Series, and the Power Rangers show quickly established that the 1995 feature film was set in a totally different canon. The only shows to pick up where a movie left of, as far as I can tell, are the ’80s Transformers and G.I. Joe cartoons. And then there’s what Marvel is trying to do with their cinematic universe, but spinning off supporting characters into their own TV shows isn’t quite the same as the way X-Files fully and totally folded in a major movie release into its serialized narrative.

So what The X-Files did in 1998 was truly unprecedented for a live-action show, specifically a show with a crazy dense continuity. Like, imagine if Lost had turned Ben Linus’ origin into a feature film, or if Netflix had released the Daredevil vs. Punisher arc theatrically. That’s essentially what the X-Files crew did between Seasons 5 and 6, releasing a movie that gave a big budget boost to the series’ alien colonization story and included a big ol’ info dump about WTF was going on.

It’s also worth pointing out that this moment–when X-Files: Fight the Future hit theaters on June 19, 1998–was arguably the most popular The X-Files has ever been. After debuting to dismal ratings in 1993 (Season 1 averaged around 11.2 million viewers a week, but was ranked 111th for the season), the show hit crazy heights in Season 5. Word-of-mouth and buzz on the very early internet had pushed it up to 19.8 million viewers a week, ranking 11th for the season. This dark show that featured a pizza-delivering vampire and a mutant Cher fanatic was far and away Fox’s biggest hit–and it was only getting bigger.

X-Files: Fight the Future came at exactly the right time, as it is positioned between the two most popular X-Files seasons ever; Season 6 only fell one spot the next season, as it was ranked 12th. The movie wasn’t a super blockbuster, but it had a respectable box office run considering it was asking a moviegoing audience to pay money to watch what critics rightly identified as a two-hour episode of The X-Files–and even at its peak of popularity, the X-Files was still a deeply weird show with an increasingly complex mythology. All this seems even more astounding when you realize they actually filmed the movie in-between Seasons 4 and 5. They had no idea at the time that the show’s popularity would keep climbing past the series-best peak of Season 4! Talk about timing!

The film, reportedly budgeted at around $66 million, made $83.8 million at the domestic box office, with a worldwide gross of $189 million. Domestically, you could argue that almost everyone that watched X-Files at the time saw this movie in the theater. The math is actually kind of perfect, with Fight the Future’s estimated ticket-buying audience size sitting squarely in-between the average audience sizes of Seasons 5 and 6. Here’s some fun math:

19.8 million (average Season 5 audience size) X $4.69 (average movie ticket price in 1998) = $92.86 million (what Fight the Future would have made if every Season 5 viewer saw the movie, which is $9 million more than it actually made)

(average Season 5 audience size) (average movie ticket price in 1998) (what Fight the Future would have made if every Season 5 viewer saw the movie, which is $9 million more than it actually made) $83.8 million (domestic box office of Fight the Future) / $4.69 (average movie ticket price in 1998) = 17.8 million people (estimated audience size of Fight the Future in theaters, two million less than Season 5’s average audience size)

(domestic box office of Fight the Future) (average movie ticket price in 1998) (estimated audience size of Fight the Future in theaters, two million less than Season 5’s average audience size) 17.2 million (average Season 6 audience size) X $4.69 (average movie ticket price in 1998)= $80.67 million (what Fight the Future would have made if every Season 6 viewer saw the movie, which is $3.1 million less than what it actually made)

So yeah, Fight the Future made pretty much exactly about as much money as it could have made–and that wasn’t such a bad haul! But it’s clear that X-Files didn’t expand its audience with its big screen gamble, and interest in the show fell off rapidly after season 6. And the show’s attempt to do what other shows have done, release a reunion movie years after the show’s cancelation, was a colossal flop. 2008’s X-Files: I Want to Believe only earned $20.9 million at the box office, an estimated audience size of 2.9 million. Y’all, even the lowest-rated episode of this year’s season 11 was watched by an estimated 3.01 million people! Yikes!

What X-Files did 20 years ago today was truly a once-in-a-lifetime happening, the only time that a massively popular live-action TV show made the jump to feature films and then kept the story going on television. And considering the specific timing of the film’s release, coming off the show’s most-watched season and leading into its second most-watched season, you gotta wonder if someone on the X-Files team had prognostication powers. And maybe they knew where the franchise would be 20 years later in 2018, and maybe that’s why this movie was subtitled Fight the Future.

Where to watch X-Files: Fight the Future