In 1983, ABC aired The Day After, a stark portrayal of the effects of nuclear war on small-town America. It was praised by President Ronald Reagan and watched by more than 100 million people, who were rattled by the ravages of atomic weapons and the suffering survivors would endure. Many thought it was the most chilling made-for-television film ever produced.

Before making that pronouncement, it might be necessary to see Threads, the BBC television movie that followed The Day After in 1984 and seemed to up the ante when it came to an unrelentingly grim depiction of life after nuclear destruction.

For some, the visceral horrors of Threads made The Day After look like an ABC Afterschool Special in comparison—a glimpse so bleak that a press screening resulted in reporters walking out, unable to take any more.

The early 1980s were a time of unease for the world’s superpowers. The United States and Russia, both possessed of a nuclear armory that could decimate the globe, were embroiled in the Cold War. The threat of annihilation was less an abstract concept than something that could actually happen. Filmmakers explored the notion less as a vehicle for entertainment and more as a public service.

The BBC had actually toyed with the Cold War and nuclear catastrophe in 1965 when they made The War Game, a quasi-fictional, documentary-style presentation that juxtaposed facts with actors. It was so disturbing that the BBC ultimately decided not to air it.

Two decades later, the broadcast network thought their audience was better prepared—or that the threat was ever more looming. The BBC hired director Mick Jackson because of his work on an episode of the science documentary series Q.E.D., which featured a nuclear bomb detonating over London and the resulting horrors. This time, he’d be given a larger budget, experienced actors, consultants (including Carl Sagan), and a make-up department primed to mimic the skin-sloughing effects of radiation. (They used Rice Krispies and tomato soup, among other tricks.)

Threads follows two families of disparate social status: The Kemps, a working-class family in Sheffield, and the Becketts, who enjoy an upper-class existence. The families are connected by Jimmy Kemp (Reece Dinsdale) and Ruth Beckett (Karen Meagher), two young lovers who are about to bring a baby into the world.

It’s not fortuitous timing for the child. A nuclear bomb comes, and the Kemps are either dead or dying. The Becketts, meanwhile, stave off immediate expiration in a fallout shelter. But there’s no particularly good news for anyone, as the ensuing chaos leads to looting, gruesome deaths, and assorted agony. Ruth is forced to eat rats for sustenance; patients’ limbs are amputated without anesthetic. (Jackson was annoyed that The Day After depicted a hospital with its electricity intact.)

Ruth manages to give birth, but it’s not much of a reprieve. For one thing, she has to bite her way through her umbilical cord. For another, she does it alone. Jimmy didn’t make it, though the audience—like Ruth—never knows why. Jackson and Threads writer Barry Hines agreed that like the people in the streets, the viewers should be largely cut off from having more context. There are no harried government officials in Threads, only frightened civilians.

Threads premiered on September 23, 1984, on BBC2 and garnered the highest ratings of that week. It immediately horrified audiences both in the UK and in the United States, where Ted Turner’s TBS cable station broadcast it with a stern warning (which you can see above). The climax, which sees Ruth’s grown daughter having a baby of her own with predictably dire results (an irradiated pregnancy is not recommended), shook viewers. Many, like The Guardian's Peter Bradshaw, tried to avoid looking at the screen. In 2014, Bradshaw recalled his viewing experience by writing that:

“At this moment, my girlfriend’s sister gave a cry or a gasp which I will never forget, and walked out of the room. I looked at her, as a way of not looking at the screen, and then I looked down at the carpet. I was genuinely scared to look up. Threads had flooded my body with the diabolic opposite of adrenaline. We all went to bed in utter silence. I have still never experienced anything like it in years of film-going, telly-watching, book-munching, culture-consuming activity.”

The BBC paired Threads with the documentary On the Eighth Day and a Newsnight panel discussion. It was only scarcely available until a 2018 Blu-ray was released. Despite its rarity, Threads was highly influential for its time. Jackson went on to have a Hollywood career, directing 1992’s The Bodyguard with Kevin Costner and Whitney Houston.

Among the petrified people watching Threads the night it originally aired was a kid named Charlie Brooker. The bleak, plausible future presented by Threads, Brooker later explained, went through his mind when he was developing the dystopian world of Black Mirror.