Be careful what you wish for – that’s the moral of this story. Because up until last year, few people outside the film industry had heard of Messrs Matt and Ross Duffer, the mild-mannered geeky twins from North Carolina. They’d made a post-apocalyptic thriller called Hidden, which didn’t do very well, and written a few episodes of Mr M Night Shyamalan’s TV series Wayward Pines that most of us didn’t see. But then they created the Netflix show Stranger Things and their lives changed forever. They promptly found themselves on all manner of red carpets, being feted as the It-boys of the golden age of television when actually they’d far rather be at home watching it.

“Honestly, I’m glad awards season is over,” says Mr Matt Duffer. “Because it’s not just the Emmys itself, there’s like a week and a half of parties leading up to it, and we’re not exactly social butterflies, so it’s kind of stressful. The kids [of Stranger Things] loved it though. They go straight onto the dance floor. Which is something I would never do.”

They had reason to celebrate. Stranger Things was nominated for 18 Emmys in total, including Best Drama, and won five Creative Arts Emmys. This confirmed the Duffers’ place on that illustrious list of sibling writing teams in Hollywood, joining the likes of the Farrellys, the Wachowskis, the Coens and the Duplasses.

Only the Duffers are more than just brothers, of course. They’re 33-year-old twins.

“We’re not actually sure we’re identical,” says Matt. (I’m sure it’s Matt only because their publicist whispered to me earlier, “Matt’s got the grey streak of hair”.)

“Yeah, and we don’t want to check either,” says Mr Ross Duffer, who has a slightly narrower face. “It might psychologically affect us, because we’ve always just assumed we were identical.”

They look it, and even style themselves similarly – with the same beards, black jeans and high tops. But the Duffers also share the same taste in movies and books, and they spend most of their days together, working out of a house near Lake Hollywood in Los Angeles, where they write, literally finishing each other’s sentences.

“It’s a great house,” says Matt. “We’ve got a ping-pong table…”

“… a pool, yeah. Total Google vibe,” says Ross.

And if one was to get carried away, the other would rein him in, the way that only a twin can. “Who better than your twin to say, ‘Hey dude, you’re acting like a douchebag,” Ross says.

“And we’re both on Google Docs all day, sitting across from each other on headphones, working on the same document,” says Matt.

At the same time?

“At the same time,” they say in unison.

When asked about creative disputes, they have to think for a minute, because they’re that rare.

“Remember we grew up watching the same movies and TV,” says Matt.

“… living more or less the same life,” says Ross.

The Duffers were always this way. Growing up in the suburbs of Durham, NC, they were “secret language” twins who went to speech therapy for years. Their mother and father – a part-time realtor and a government researcher, respectively – understood, “but no one else,” Matt says. Soon afterwards, they were making films together on a Hi8 video camera, like their take on The Godfather featuring stuffed animals and mops.

“We called it The Stuffedfather,” says Ross. “Parts one, two and three. And, yeah, three didn’t live up to one and two.”

Born in 1984, they were a few years too late for films like ET, Poltergeist, Gremlins and Nightmare On Elm Street (the latter two made the same year) – all the films that would inspire Stranger Things. But that didn’t stop them. They watched them on VHS, gorging on 1980s movies in the 1990s. The Goonies had a big effect, as did Stand By Me, for the way they portrayed kids. “It just blew our minds,” says Ross. “So many people write this Disney version of kids, but those films didn’t condescend. The way they communicated, there’s so much back and forth and overlapping dialogue… it’s messy.”

They went to a little hippy private school where they called their teachers by their first names, but were soon plunged into a big public high school. It was terrifying for the nerdy twins who didn’t play sports. But filmmaking was their ticket to popularity even then. “We’d make videos for class projects and get As, so the cool kids were like ‘Make a video for me’,” Matt laughs. “And they totally took advantage – I had no life at weekends because I was making videos for cool kids to get an A.”

Still, it was a happy time. Part of the reason the Stranger Things era – the 1980s – has captured our nostalgic imagination is because today’s filmmakers were children back then. And childhood was much simpler and freer, before the internet, and cellphones. “Now you can track your kid with GPS,” says Ross, “but we would go out to make our films, and have these amazing adventures and our parents had no idea.”

Perhaps it’s just the way nostalgia works. “It’s like that Woody Allen movie, Midnight In Paris,” says Matt. “No one’s ever happy in the time they’re in.”

“Yeah, they’ll be looking back on this with nostalgia soon,” Ross says. “Oh, remember the iPhone 6! How adorable!’”

They moved to California to study film at Chapman University in Orange County, together, and made a series of short films after graduating a decade ago. Their big break came with Hidden, starring Mr Alexander Skarsgård, about a family locked away in a bunker for mysterious reasons. But it wasn’t exactly a hit. Ross has said since that “Hidden was a great experience because we know what it’s like to fail. And we know it will happen again.”

The spark for Stranger Things came after watching Prisoners, a dark psychodrama starring Mr Hugh Jackman in which a child goes missing and his father is driven to torture and violence. Tonally, it’s a world apart from the innocent delight of Stranger Things. “Yeah, but a child does go missing,” says Ross. “And we’re childish, so we were like, ‘What if you do something supernatural? What if there’s a monster?’ Then we started thinking of conspiracy theories and ended up setting it in the 1980s.”

The pitch sounds like a home run on the face of it: “What if Mr Steven Spielberg directed a Mr Stephen King book?” But instead, it was roundly rejected. “Because who the fuck are the Duffer brothers? That was the main thing!” says Matt. “But also because we had child leads and it was set in the 1980s. Which of course are the things that made it work. So that’s why you can’t take that stuff seriously.”

But they found a champion in producer Mr Shawn Levy, who had made Arrival and directed Night At The Museum. So Netflix took a chance, as did Ms Winona Ryder, who had been quiet for a while, and was poised for a comeback. Meeting her, Matt says, was “surreal, we’re such huge fans”. When they were growing up, Ms Ryder reigned supreme. Their first meeting ran for four hours; it turns out they have a lot in common.

“I thought we knew our 1980s movies, but not compared to her,” Matt says. “She’s seen stuff I haven’t even heard of, and her memory is insane. We can show her a cut and she’ll say, ‘In take two, I touched my hair at this line’. She keeps all the dailies from her movies in her house, and she knows every take. She just has a very interesting brain. Like she’s obsessed with continuity. But in this business, the best people often tend to have an obsessive-compulsive tendency. I certainly do.”

The rumours are true: working with kids does present challenges. And it’s not as though the brothers have hands-on experience. Ross is married, and Matt has a girlfriend, both living in Los Feliz, in LA, 15 minutes walk from each other. But neither are parents, not yet. “It’s a good thing, because that child would be neglected,” says Matt. “We work basically all the time.” So it’s been a learning curve, dealing with the giggling issue, for instance.

“Yeah, Millie [that’s Ms Millie Bobby Brown, who plays Eleven] will be giving a serious emotional performance and the boys will be just goofing off,” says Ross. “They also don’t work as hard as adults on account of labour laws.”

“Yeah, the government requires them to be educated,” says Matt, rolling his eyes. “So no night shoots for several days in a row. We can’t just work them to death. But there are perks, too. Because you have more power over them. If I want Winona to move to that window, it’s a discussion. If it’s a child, you can grab them and move them.”

They can still grab them for now, but that’ll soon change. The kids are now aged between 13 and 16 and growing fast. In season one, voices were breaking (Mr Gaten Matarazzo, who plays Dustin, in particular). So, as they create season two and beyond, they need to adapt accordingly.

“You can’t freeze the story in time, you have to do what Harry Potter did,” says Matt. “That’s my argument to Netflix. It’s fun watching them grow up. You have to lean into it, and write different stories. It forces the show to evolve.”

They had a lovely time writing season two, but then the pressure of living up to the success of the first season hit home. “It was like, ‘Oh amazing, people like the show, and we’re in this amazing house and life is wonderful!’ Then it hits you: ‘Holy shit, we have to write these scripts!’” says Ross. That first flush of success has faded, the parties are over (thank goodness), and the brothers are back to their quite studious, movie-geek lives. Ask them what they get up to in their downtime, they laugh. “Not a whole lot!” Matt says. “We like binge shows like anyone, but mostly I play video games on a big TV, or board games. Pretty nerdy. I’m still in the same apartment I was in five years ago – that’s my life. I do kind of want a house now, with a garage.”

They know what they’re working towards – they’ve known how it’s going to end for about a year now, in season four, more than likely. “It’s hard to imagine going past season five. I get in trouble for saying stuff like this!”

So what can they tell us about season two – or Stranger Things 2, as it is billed – which fans can binge-watch over the Halloween weekend?

Ross grins. “Well, the sequel cliché is, it’s bigger and darker. And it is, I think.” It builds to a climax, it moves quickly, “because I can’t stand the glacial pace that most television moves. We were raised on movies, where things are faster.”

How are they coping with the hype building up to the release of the new season?

“Yeah, there’s pressure,” Ross says. “I can tell you this: You don’t want to make Home Alone 2, which is exactly the same beats as the first movie.”

“You know what, I’d rather we made Temple Of Doom than Home Alone 2,” says Matt. The point is that Indiana Jones’ second outing, Temple Of Doom, wasn’t universally liked. “It’s still disliked, even by Spielberg!” he says. “But I don’t care because it resonated with a lot of kids. It’s a big part of our childhoods and there are images from that movie that sear themselves in your brain…”

“… like monkey brains and ripping out the heart,” says Ross finishing the thought. “So yeah – even if we end up being Temple Of Doom, I’m fine with it.”

Stranger Things returns to Netflix from 27 October