In the recent reboot of “The X-Files,” mysterious cases leave Mulder (David Duchovny) and Scully (Gillian Anderson) as flummoxed and searching as ever. Photograph by Ed Araquel / FOX

I have a vivid memory of the premiere of “The X-Files.” It was September, 1993, and I was thirteen years old. That summer, I’d discovered horror movies and watched “The Thing” and “The Silence of the Lambs”; I’d also read “Communion,” Whitley Strieber’s best-selling memoir about being abducted by aliens. Like a lot of people back then, I was fascinated by U.F.O.s—in the late eighties and early nineties, alien abduction was a thing. Whole episodes of “The Sally Jesse Raphael Show” and “The Maury Povich Show” were dedicated to it. I couldn’t wait for “The X-Files.” I was so certain that the series would be great that, when the pilot aired, I taped it (a rarer, more labor-intensive undertaking in those pre-DVR days).

The weaknesses of “The X-Files”—tendentious dialogue, an alien conspiracy that made no sense—were obvious from the beginning. Still, the show had two real strengths, and they grew with time. The first, of course, was the gentle, intellectual romance between Mulder and Scully. The second was a vibe of improvisational zaniness that remained undiminished for nearly nine years. Fox’s advance publicity had made “The X-Files” look like a straight-faced, alien-themed procedural. (What a drag that would have been.) In fact, the show was sly, hilarious, and unpredictable—it was, in a word, unprofessional, in the best sense. Often, it achieved that rarest of artistic virtues, a genuine feeling of spontaneity. Using the same basic setup, “The X-Files” could present all sorts of stories: a gross-out episode about a giant humanoid flukeworm (“The Host”); a satirical, Rashomon-style retelling of an alien abduction (“Jose Chung’s ‘From Outer Space’ ”); a B-movie story about a possessed tattoo, voiced, cheekily, by Jodie Foster, which urges a man to commit murder (“Never Again”); even an episode filmed in the style of the reality-TV show “Cops” (“X-COPS”). Against this material, Gillian Anderson and David Duchovny turned out to be ideal straight men. They could carry the show anywhere, even as they communicated, through a slight strain in Mulder’s voice or a small twist in Scully’s lip, that they were in on the joke. Nine seasons of flying saucers would have been unbearable. Because of its playfulness, the show was a joy.

The main problem with the two “X-Files” movies, “Fight the Future” (1998) and “I Want to Believe” (2008), was that they were formally incapable of capturing the series’ madcap diversity: they could tell only one story at a time. But the new, six-episode “X-Files” miniseries, which premières this Sunday, is as weird and spontaneous as the original show. The first episode, “My Struggle,” isn’t good: it’s all leaden, paranoid exposition—a too-accurate evocation of the show in its ponderous, alien-conspiracy mode. (Perhaps, as with Karl Ove Knausgaard’s opus, we’ll find out why it’s called “My Struggle” in the sixth installment.) The next two episodes, however, recall vintage “X-Files.” The second, “Founder’s Mutation,” is a gothic mashup of “Rosemary’s Baby” and “Carrie,” in bad taste to just the right degree; the third, “Mulder and Scully Meet the Were-Monster,” is a meta-farce in the tradition of “Jose Chung’s.”

In the run-up to the miniseries, fans have wondered just how dated it will seem. When the series débuted, Anderson and Duchovny were twenty-five and thirty-three; they’re now forty-seven and fifty-five, respectively. Last month, on “Saturday Night Live,” Ryan Gosling, Kate McKinnon, and Cecily Strong played countrified victims of an alien abduction, evoking, hilariously, the sheer absurdity of the whole scenario (the aliens, McKinnon said, had dropped her out of their spaceship and “onto the roof of a Long John Silver’s”); a few weeks ago, a skit on “Jimmy Kimmel” imagined Mulder and Scully’s awe at the sight of an iPhone. As anticipated, the miniseries feels like a time capsule. There’s no attempt to incorporate new trends in horror storytelling, such as the sprinting zombies of “28 Days Later” or the torture-traps of “Saw” or “The Cabin in the Woods.” Even the fashion has a nineties vibe. At one point, Mulder talks about looking something up on “the Net.” He and Scully are as dowdy and shambolic as ever.

I, for one, am glad. I would’ve been disappointed if “The X-Files” had returned as a slick, modern reboot. Today, pop culture worships badasses. Everyone cultivates a fashionable, skin-deep vulnerability; underneath, they’re superheroes with jujitsu skills and heads full of put-downs. “The X-Files” pre-dates this trend. Often, Mulder and Scully were confused and powerless; in the end, the bad guys got away, slinking back into the woods (or the Pentagon) to lurk forevermore. In that sense, “The X-Files” was pretty realistic, when you think about it.

There are other reasons why actually updating “The X-Files” would’ve been a mistake. For one thing, it’s already happened: in 2008, the TV show “Fringe,” co-created by J. J. Abrams, Alex Kurtzman, and Roberto Orci, gave us a sleeker, revved-up version of “The X-Files,” complete with a secret conspiracy and monsters of the week. (“Fringe” is hard to top: after a slow start, it became an exceptionally thoughtful and moving series, and it took the “X-Files” formula in surprising directions.) More fundamentally, nostalgia is central to the appeal of “The X-Files.” It’s true that, back in 1993, there was an au-courant quality to the show: it captured a moment of post-Cold-War, dawn-of-the-Internet paranoia, and capitalized on the alien-abduction craze. Essentially, though, “The X-Files” had its gaze set firmly on the past. Huddled in his subterranean office, Mulder was like a college-radio d.j. surrounded by old records; he was a connoisseur of the weird, a gatherer of nerd-knowledge about the sci-fi and horror stories of yesteryear. As an investigator, that knowledge—shared with Scully using an old-school slide projector—was his tactical advantage.

Scholars have a term for our fascination with the science fiction of the past: they call it “retrofuturism.” In the “Oxford Handbook of Science Fiction,” Elizabeth Guffey and Kate Lemay offer an elegant definition of the term: “Where futurism is sometimes called a ‘science’ bent on anticipating what will come,” they write, “retrofuturism is the remembering of that anticipation.” Retrofuturism tends to be both celebratory and regretful. On the one hand, the retrofuturist sensibility is drawn to old visions of the future because today’s have lost their appeal; on the other, it recognizes that those old visions had their downsides. Steampunk, for example, is attractive precisely because it rejects the disembodied corporatism of the digital world; still, the vision of the future in the film “Snowpiercer” is both refreshingly analogue and brutally Dickensian. (That’s not to say that retrofuturism is always ambivalent: “Star Wars” is, among other things, an upbeat retrofuturist response to the drug-addled sci-fi of the sixties and seventies.) “The X-Files” was a retrofuturist show. It celebrated the wide-eyed sense, prevalent in the forties, fifties, and sixties, that science was about to change everything. It also recalled the darkness of the Cold War, when individuals felt powerless against vast geopolitical forces, and science brought us to the edge of thermonuclear doom.

Because we live in a moment of reboots, remakes, and revivals, we seem to be surrounded by retrofuturism. Superhero movies, with their emphasis on mad-science mutation, have a retrofuturist appeal. So do the rebooted “Star Wars,” “Star Trek,” and “Mad Max.” Even “Interstellar,” in many ways a forward-looking film, also looked back to the sci-fi of the past. If you’re of a theoretical cast of mind, you might wonder what it means to be nostalgic for a retrofuturist show like “The X-Files.” Is it possible, “Inception”-style, to square retrofuturism? Can you look back ambivalently at the way people used to look back ambivalently at a vision of the future?