How did Stranger Things become Netflix's biggest show?

What constitutes a hit for the streaming service is sometimes unclear – the company famously refuses to release viewing figures – but when they announced record third-quarter results for 2016, Stranger Things was one of the series credited, while leaked numbers appeared to show it outperforming Kevin Spacey in House of Cards. Series two was commissioned almost immediately.

“When we cast Winona back in 2015, she wasn’t doing a lot of movies and had never done television – I’m not sure she would have met with us otherwise,” explains Stranger Things producer Shawn Levy, in a drab office at the edge of the show’s Atlanta-based set. “Then, after season one, the Duffers and I got calls from a lot of very famous actors who wanted to be a part of season two, and well-known directors almost begging to direct an episode.”

Ryder certainly had a part to play in Stranger Things’s success – she was single mum Joyce Byers, whose search for her missing son Will reminded everyone how mesmerising she could be. “We met up with her for a cup of tea and ended up in this four-hour-long conversation – she had the fragility we needed,” Ross Duffer says. “The script was rewritten so the character was based on Winona herself, to a degree.”

Also significant is the imprint left on the brothers by the work of Steven Spielberg and Stephen King. “There was a very specific feeling I had when I was reading Stephen King books in my bedroom when I was a kid and we were trying to capture that and put it on screen,” says Matt. “We hung out with a group of nerdy friends playing games. There was this sense that if you went into the woods you’d find a treasure map and go on an adventure.”

To the surprise of Hollywood, if not the Stranger Things team, adults really loved the kids. “The conventional wisdom in film and TV is you can’t make something starring kids that isn’t for kids,” says Matt. “We saw over a thousand people for these parts because we really wanted kids who didn’t feel that they belonged on television and felt authentic.”

Finn Wolfhard, Gaten Matarazzo and Caleb McLaughlin as Mike, Dustin and Lucas – the three nerds trying to find their missing friend Will, played by Noah Schnapp – all shone, but British actor Millie Bobby Brown, 13, utterly stole the show as the haunting Eleven. Brown’s family moved from Bournemouth to Florida when she was eight, and then on to LA after her drama teacher told Brown’s parents that she has “instincts you cannot teach”. Stranger Things isn’t quite her debut; she had three years of bit parts before being cast, and when RT meets her on set she’s as assured as a veteran.

Discussing the show’s success, for instance, she says, “Instagram followers started to go up, I started to get more messages, my friends that I hadn’t spoken to in three years started to text me again, and I was like, ‘Hmm, OK, I see where this is going…’” she smiles. “Eleven is a freak, an outcast, she’s got a shaved head and she embraces it all – and that’s why people just relate to her.”

Some traumatic scenes – being locked in a cell, running from her captors and battling a giant monster – look alarming to film, but she shrugs this off. “The Duffers are really sensitive and say, ‘We’re going to give you however long you need,’” she says. “But honestly? Sometimes I feel like the happy scenes are a bit boring for me. I love to cry in a scene and I like action scenes where stuff is happening.”

Asked about the risk of becoming a child star casualty, she rolls her eyes. “I don’t know if I’ll keep doing it or go off to college but all of us enjoy going on set every day. We’re not looking for longevity, we’re looking for the fun of it.”

The hardest part, she confesses, has been dodging questions about season two. At the end of season one it looked like Eleven had been killed, and she couldn’t tell anyone she was coming back. And for that reason, much of season two is still under wraps.

The problem is, Matt points out, that following a breakthrough, unexpected hit isn’t easy. “When we were making this thing two years ago no one was paying attention,” he shrugs. “Doing season two with this expectation level is definitely daunting. We’ve had to avoid most social media, for a start.”

Will there be a third season? “It’s not wrapped up this season – there’s too much to deal with,” says Ross. “Hopefully there will be at least four more [series], but I think there’s going to come a point where we start stretching credulity. Where you say, ‘Hey, why aren’t these people leaving town?’ I think we’ll know when to quit.”

By Stephen Armstrong

Everything you need to know about Stranger Things 2