It’s Saturday morning, I’m 8 years old, and I’m in the kitchen. Lord knows why, but now is the time that my mom has decided to quiz me on my times tables, specifically those treacherous 7s and 9s. She’s chosen to do so at around 9:50 a.m., ten minutes before the most vital half-hour of my 3rd grade self’s week: X-Men. At 10 a.m. every Saturday, the X-Men theme would sound out from our den like an alarm, signaling the arrival of very serious TV.

For me and nearly every kid born in the early-to-mid ’80s, a generation now immersed in appointment TV, X-Men was our very first obsession. You could miss episodes of Teenage Mutant Ninja Turtles or G.I. Joe, subconsciously sure that Splinter would be rescued and Cobra Commander vanquished. That wasn’t the case with X-Men, a cartoon that had the audacity to end episodes on cliffhangers, let subplots simmer for a season, and sometimes even kill characters.

The TV landscape was drastically different when X-Men’s first episode, “Night of the Sentinels,” aired 25 years ago. The most-watched shows of the 1992-1993 season were sitcoms and done-in-one dramas like Murder, She Wrote. That’s a far cry from today, when the most buzzed-about shows (Game of Thrones, Stranger Things, The Good Place) build from episode to episode as their worlds evolve and expand. That wasn’t the case in 1992. Sitcoms didn’t do that, dramas didn’t do that, and animated shows definitely didn’t do that.

The super-cartoons of the ’70s and ’80s presented tidily defeated villains, one per episode. That was still the case in the ’90s, as evidenced by X-Men’s peer Batman: The Animated Series. Debuting just under two months earlier, the deeply noir Batman: TAS elevated the Saturday morning cartoon into a cinematic experience. With instantly recognizable character designs and a palpable, moody atmosphere, Batman is a masterpiece. But while it pushed boundaries for writing and animation, it played it safe when it came to serialization. You could miss an episode of Batman, as pretty much every episode ended with the villain in Commissioner Gordon’s hands and Batman safely brooding in the Batcave. Superhero cartoons, despite leaping forth from the heavily-serialized pages of Marvel and DC comics, never attempted to mimic their source material’s storytelling structure.

X-Men supervising producer Will Meugniot told Decider via email that the minds behind Marvel’s mutant show wanted to do something different. “Our goal was to emulate the experience of reading the actual comics, rather than delivering a dumbed down version as had been done in the past by shows like Super Friends and Spider-Man and His Amazing Friends, and that necessitated more complex stories with drawn out character arcs.”

This is the status quo that X-Men disrupted, like a Sentinel crashing through a three-story-tall mall window.

With the “Night of the Sentinels” two-parter, X-Men let kids know that this was a cartoon that wasn’t going to mess around–and that was the plan all along.

“Those of us who grew up reading the classic Marvel Comics of the Silver Age understood that the reason Marvel’s characters had never caught on in animation as strongly as they did in comics was that Marvel had always been willing to sacrifice their integrity when doing ‘kids’ shows,” said Meugniot. “The mantra from our side of the table was, ‘Don’t betray your roots.’ The comics themselves were the inspiration for our serialized format.” X-Men story editor Eric Lewald also told Decider via email that mini-series of the ’70s and ’80s, like I, Claudius and Lonesome Dove proved to them that audiences could handle serialized stories.

There’s an intricacy to X-Men’s long-form storytelling that wouldn’t become the norm until the late ’90s with shows like Buffy the Vampire Slayer. “Night of the Sentinels” alone introduces a new character (the chili-fries-eating mall babe Jubilee) and new recurring villains (the Sentinels). Morph, a shapeshifting X-Man, actually dies in battle against the Sentinels. Just a few years after G.I. Joe anxiously retconned Duke’s death so as to not upset kids, this Saturday morning kids’ show blasted away an X-Man in the pilot!

And Morph isn’t the only sacrifice: the beloved blue Beast gets arrested in after the X-Men’s failed raid on the Mutant Control Agency and then spends all of Season 1 in prison.

Even the very first shot of “Night of the Sentinels,” a news report on the feral and is-he-naked Sabretooth trashing a police car, has extensive ramifications. Sabretooth returns in episode 3 (“Enter Magneto”) when he literally crash’s Beast’s bail hearing, and continues into episodes 4 (“Deadly Reunions”) and 6 (“Cold Vengeance”) as Wolverine fights his old nemesis in the X-Mansion and the Arctic.

A season’s worth of story, from Sabretooth to the Sentinels, is established in just those two episodes.

And the serialization doesn’t stop there! Magneto’s first encounter with the X-Men spans two episodes, with different combinations of X-Men countering his attacks on a missile facility (“Enter Magneto”) and chemical plant (“Deadly Reunions”). Wolverine’s beef with Professor X over taking in Sabretooth causes him to leave the team, a sabbatical that separates the X-Men from their poster boy for two episodes (“Captive Hearts” and “Cold Vengeance”). Gambit’s total shadiness in episode 7, “Slave Island,” makes the entire team question his loyalty when a time-traveler with zero chill named Bishop accuses him of being a traitor (the “Days of Future Past” two-parter). Character relationships also deepened over time, with Wolverine taking Jubilee under his wing and Gambit and Rogue acting like an animated Sam and Diane. The aforementioned “Slave Island” ends with the X-Mansion totaled, a mystery solved next week when the Juggernaut shows up (also in that episode: Beast, still chilling in a cell).

If Season 1 seems tightly plotted, that’s because it was designed that way–even though that was totally against the cartoon rulebook. “Mark [Edens] and I laid out the 13 stories of Season 1 in detail as a single 10-page premise before any writer started to script,” revealed Lewald. “Mark and I thought of it as one story–start by introducing the Sentinel threat, then resolve the story with episode 13’s defeat of Mastermold. And since no one was assured of more than the first season, that very well might have been it.”

Keeping viewers up to speed every week was a quick refresher, airing just before the opening credits and after a voiceover from Cyclops proclaiming, “Previously, on X-Men,” accentuated by an electrifying graphic.

The idea to include this catch-up came from the Fox network exec paired with X-Men, Sidney Iwanter, who championed the ambitious structure from the get-go.

X-Men’s first season also succeeded on a thematic level, with every story unified by the central theme of persecution. The Sentinels represent humanity’s response to mutants, and they pop up in “Night of the Sentinels,” “Slave Island,” the “Days of Future Past” arc, and the (absolutely fantastic) season finale “The Final Decision.” Magneto’s appearance in episodes 3 and 4 lets the show contrast his reaction to bigotry with Xavier’s, thus making their team-up in episode 13 (again, absolutely fantastic) resonate.

We see extreme examples of persecuted mutants (the sewer-dwelling Morlocks in episode 5) and an extreme example of a mutant doing the persecuting (Apocalypse in episodes 9 and 10). Not only does this TV season hang together as a riveting four-and-a-half hour story, it dissects the X-Men’s central theme with way more skill than the Weapon X program.

This was not an easy task. While modern animated shows like Avatar: The Last Airbender and Star Wars Rebels are heavily serialized, the level of strategizing it took to pull this season off in 1992 would have even given Cyclops a headache. There was a real danger to it, as Lewald explained, because a delay in animation early on would set off a chain reaction, pushing back the debuts of completed episodes that could be aired were they not part of a continuing narrative. A delay did happen with episode 3, meaning that X-Men wouldn’t settle into a weekly groove of airing new episodes until January 1993.

“The first episodes weren’t even cut digitally–we were cutting film,” said Lewald. “We would have to wait months to see if what we wrote, drew, and recorded looked right and cut together as we had imagined. We finished the entire first season of scripts before we saw a foot of animation. There was no way to use what we learned in one episode to help write the next one. We just had to trust our instincts.”

The brains behind X-Men also faced constant pushback from both Marvel and Fox regarding the show’s serialized structure. “The strongest opposition to creating a show that was faithful to the Marvel way of doing things came from Marvel, which galvanized us into trying to do it right,” said Meugniot. “We knew our audience wasn’t stupid and that they were frustrated by being talked down to. Our best argument was that we’d been kids when Stan [Lee] started the more adult approach to superhero stories and we loved it and wanted replicate it for our viewers.”

It worked. I felt the seismic shift of this show as it reverberated throughout my 3rd grade class and, honestly, my own life from that point forward. At the age of 33, I see that X-Men’s animation is rough, that the plots play fast and loose with logic at times, and the voice acting is sometimes over the top. But adult me, the TV critic, also sees that those elements combine to make X-Men an edgy, almost punk rock show. This show gave a middle claw to how cartoons were supposed to be done.

The scripts distilled each X-Man down to their fiery core (Rogue and Gambit have never, ever been better than they are here), and those dramatic performances amped up the rushed animation and gave the show a soul, captivating a massive audience as it breathlessly raced towards a barnburner of a season finale. It’s fast, it’s passionate, it’s adventurous, it’s pure guts and pure heart. This show crackles with energy, as if Gambit himself had charged it.

This show ignited not only a 25-year-long love for the X-Men, a love that’s now encoded in my DNA, it gave me the craving for serialized storytelling that I still feel today.

Unfortunately, the very thing that made Season 1 so kinetic was the one thing Fox shut down for future seasons. To avoid production headaches, future seasons of X-Men shifted to a more episodic storytelling style, although the writers didn’t totally abandon their mission. Instead of having the plots knock into each other like mutant dominos (but not the mutant Domino), Season 2 featured a season-long subplot involving Professor X and Magneto in the Savage Land, usually as two-minute-long action sequences at the top or bottom of an episode. Season 3 worked in serialization by including the 5-part “Phoenix Saga” and 4-part “Dark Phoenix Saga,” although episodes airing wildly out of order around this time caused Jean Grey’s death and return to go by with minimal impact (watching the episodes in script order rectifies that).

But X-Men’s gambit paid off. Production troubles aside, Season 1 got a whole generation of viewers hooked on serialization for the first time while also raising the bar for storytelling structure in animation. Lewald and Meugniot knew the trouble was worth it.

“We found out fast that everything risky that we had fought for–serialization, adult stories, fast pace, serious drama instead of light comedy, respecting the books–worked with the audience,” said Lewald. “ X-Men: TAS, showing on new little 4th-place Fox network, not only premiered in January at number one in its time period, it was soon grabbing over half of the TV viewers in the country, more than the three ‘big’ networks combined.”

“While we were building our inventory to start regularly airing in January, Fox Kids was taking votes in their Thanksgiving Take Over event, in which kids got to ask for the shows they wanted to be shown on Thanksgiving morning,” said Meugniot. “It was kept secret at the time, but virtually 100% of the requests were for X-Men. We were validated with the network.”

And that’s how a Saturday morning superhero cartoon defied all the rules and became an entire generation’s first-ever TV obsession.

For more information about the making of X-Men, you can order Eric Lewald’s book Previously On X-Men: The Making of an Animated Series, available this November from Jacobs/Brown Media. You can learn more about the book at its website.

Where to stream X-Men