Its morbidity, even at the expense of being moving, can largely be attributed to director Nicholas Meyer, who fought at every step for his to be a brutally straightforward depiction—something he undertook as a “civic responsibility,” as he told The Washington Post in ’83. Meyer inherited the project, which was dreamed up by ABC executive Brandon Stoddard, right when he could have just been riding high after Star Trek II: The Wrath Of Khan, making more escapist blockbusters about far more charismatic destructors. Instead, he took on a deeply, nauseatingly well-researched and graphic script from Edward Hume, then approached the project as a “public service announcement,” not entertainment. “From my perspective it isn’t a very good movie,” Meyer said in a recent interview. “And more than that, it was not intended to be a very good movie.”

Meyer’s right: The Day After isn’t a very good movie, at least not in the usual sense. It’s pretty sluggish for its entire first hour, poking around the farmlands of Lawrence, Kansas while introducing its various milk-fed, salt-of-the-soon-to-be-salted-earth characters. After sitting through their various standard family drama subplots for an hour, you kind of can’t help but wonder when they’re gonna get to the genocidal fireworks factory. And after the bombs finally do drop, its second half suffers from that aforementioned clumsy editing, as characters disappear for long stretches, get desultorily dispatched off-screen, or just end up abandoned altogether.

Time also hasn’t been particularly kind to its special effects, which, even by 1983 standards, have a distinctly painted-on feel. The exceptions are the tangibly scarred downtown streets and blown-out buildings, which were smashed up by a production that descended on Lawrence like its own purgative fire. Meyer then reportedly paid hundreds of locals $75 a head to shave them bald and plaster on latex scars until they resembled sickly, molting chickens, which the townspeople eagerly took on as a fun little brush with movie magic.

But in the sense that movies should provoke some sort of emotional reaction, The Day After is unusually effective—largely due to that reliance on using real people. Meyer actually didn’t want to use any famous actors, concerned it would only take viewers out of it and reassure them that this was all just some Hollywood fantasy. But after the network said it needed someone it could sell to foreign markets, in stepped Jason Robards—who was coming off Oscar-recognized turns for All The President’s Men, Julia, and Melvin And Howard—to play the kindly Dr. Oakes, who somehow survives the blast by ducking down in the front seat of his car (they don’t build ’em like that anymore), then staggers 10 miles back to the University Of Kansas to lead triage efforts for the survivors. The weight of the world, as always, rests on Robards’ eyebrows here, but even his performance feels subsumed by the mass of shattered, anonymous faces that surround him.

Of course, time has lessened this effect as well: The Day After is full of people you’d recognize now—and even a few you would have back in ’83. JoBeth Williams, who plays Nurse Bauer, was in the middle of a hot run that stretched from Stir Crazy to Poltergeist to The Big Chill. As the worldly Professor Huxley, John Lithgow was fresh off his Oscar-nominated breakout in The World According To Garp—which makes his relatively minor role seem like a squandered opportunity. There’s also Animal House’s Stephen Furst as one of Lithgow’s students, and a brink-of-stardom Amy Madigan as a pregnant woman who’s understandably conflicted about bringing a child into the newly destroyed world. Most distractingly, there is Steve Guttenberg, in the fulcrum between Diner and Police Academy, playing a college student whose Midwestern twang flits in and out—and who’s first introduced in his tighty-whities.

And finally, there is Northern Exposure’s John Cullum as the patriarch of a family riding out the blast in its cellar. At the time, Cullum was more of a Broadway star, but was nevertheless such a familiar, comforting presence, it fell to him to warn ABC viewers of the “unusually disturbing” images they were about to see—right after the ABC announcer explained why they wouldn’t be getting Hardcastle & McCormick that night. (Would Hardcastle be able to take down that gang of car thieves? Would we live long enough to see it?!)

Even in their relatively primitive state—even when surrounded by the intermittent amusement of the Gute, strutting around in ’80s jeans tucked up to his armpits—those images are still plenty jarring. The attack sequence in particular remains riveting, a series of clever crosscuts between government missile test footage and scenes of all those average Midwesterners, watching ominous vapor trails appear over gazebos in the park, before being flash-frozen in the blast. Though significantly toned down from the script’s original plans to show skin and eyes melting, or faces blasted from skulls, it’s arguably even more effective in its restraint. Maybe it’s the sentimentality brought on by new parenthood, but I haven’t been able to shake the image of a mother holding her baby as they’re transformed into glowing X-ray skeletons, evaporated in an instant.

In the aftermath that takes up its back hour, The Day After becomes a genuine horror film as its characters begin to succumb to radiation poisoning, their hair and teeth falling out as they shamble through scorched fields strewn with bloated animal corpses and dead family dogs, swarming with flies. Befitting the deathly pallor, Meyer imbues these scenes with classically gothic imagery: a bell struck by an unseen hand wielding a brick summons survivors from the crypts of their shelters; a lighthearted conversation between Robards and Williams is interrupted by a bandaged woman sitting up into frame and shrieking; a preacher gives a sermon inside the crater of a church, a burned crucifix dangling behind him; a young woman sitting in the pews begins suddenly bleeding from between her legs into her white dress. A bit heavy-handed, maybe—but then, there’s nothing subtle about apocalypse. And as the end title card reminds us, even this grisly depiction is still “in all likelihood, less severe than the destruction that would actually occur,” not to mention wholly more cinematic.

Just by attempting to show that devastation, its critics preemptively argued, The Day After was making a political statement. Conservative commentators like William F. Buckley decried the film for being anti-deterrence; “No Nukes” protesters embraced it as the same, holding candlelight vigils and rallies around its airing. For his part, Meyer rebuked both sides: “I don’t want a conservative backlash saying ‘Oh, this is just the Jews in Hollywood, this is just liberals in Hollywood, mounting their soapbox,’” he told the Post (a statement that still feels sadly contemporary). He resisted the idea that The Day After had any political message beyond, as he told an Australian news station, “that nuclear war is bad for you, and that if a nuclear bomb goes off it’s going to ruin your entire day.”

As such, the film deliberately obscures who shot first. “What does it matter?” asks one survivor, a college student seen earlier confidently spouting off about geopolitics. Lithgow’s professor responds by morosely quoting Einstein: “I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.” Who cares about politics when we’re all sifting through the rubble? Nevertheless, it raised enough hackles to prompt a tense special edition of Nightline that immediately followed, with nuclear freeze advocates like Carl Sagan squaring off against Buckley, Henry Kissinger, and Robert McNamara. (Watching that debate now, it’s dismaying how relevant the discussion feels still—not to mention how much more respectfully it’s conducted than any given TV discussion today.) And the movie famously influenced Ronald Reagan, who wrote in his diary that watching it “left me greatly depressed.” After signing a 1987 nuclear treaty with the Soviet Union’s Mikhael Gorbachev, Reagan sent a telegram to Meyer, saying, “Don’t think your movie didn’t have any part of this, because it did.”

Reagan is never mentioned by name in The Day After, though he did make a sort-of-cameo in the form of an actor doing a passable impression of his halting wheeze in a radio broadcast, aimed at reassuring survivors that there had been “no surrender, no retreat from the principles of liberty and democracy”—ironically juxtaposed with stunned, soot-covered mole people who could really give a shit. After this scene was denounced as tantamount to a political attack, the actor was overdubbed with another, more generically patrician voice for later versions.

Like the scene where Cullum’s farmer is given the laughable, FEMA-sourced advice to just “scrape off” his irradiated topsoil, it’s in moments like these that The Day After’s actual—and again, sadly relevant—message makes itself known: Should we be hit with nuclear missiles, no one will really know what to do about it. Hell, if it happens sooner rather than later, we won’t even have the cold comfort of a president who can offer up some eloquently empty words.

That’s why, watching it today, the most chilling aspect of The Day After isn’t the bombs, or their grisly aftermath. It’s all the scenes leading up to it, as people go about their lives with snatches of news broadcasts overheard—and ignored—in the background reporting on some tense, but relatively minute skirmish in Berlin. Even Lithgow’s politically informed, astutely cynical intellectual laughs off the idea of escalation, saying he has symphony tickets. The soldiers stationed around Lawrence’s missile silo joke about nuclear war infringing on their weekend fishing plans. Robards’ wife sees an alarmist special bulletin, moans, and says she just wants to go to bed. Even as the world teeters on the edge, Robards pauses to ask, to no one in particular, “Do you understand any of this?” Throughout, the threat of cataclysmic war remains a distant, inscrutable, headache-inducing hum, something to be switched off as soon as it becomes too complicated to follow. If it were made today, you could easily cut in shots of people paging listlessly through Twitter.

“We knew this could happen for 40 years. Nobody was interested,” Madigan says during one of the film’s more on-the nose moments. Yeah, well, it’s been another 34 since then, and people aren’t exactly getting worked up about it today either, even as nuclear brinkmanship has now expanded to include some far more unpredictable new players, and the codes put in the hands of impulsive zealots who, unlike Reagan, don’t have the capacity to reflect somberly on much of anything. In the meantime, we’ve only become even more numbed to nuclear war by decades of way better-looking mushroom clouds dotting our TV and movie screens—just one more obstacle for a superhero to come and throw CGI at. If The Day After has anything to warn us about today, it’s that we’re still woefully unprepared for something we’ve been worrying about—and shrugging off—for as long as we can remember.