Since the first episode of Stranger Things aired in 2016, it has become a cultural phenomenon. It's hard to imagine a world where the Netflix series wouldn't have been a hit, though there was a time when David Harbour, who stars as fan-favorite Jim Hopper, wasn't so hopeful about the show's success.

The fourth season of Stranger Things recently hit over 1 billion hours of viewership during the first 28 days after its release in July. The only Netflix project that reached the same milestone was the Korean language series Squid Game, which accumulated 1.65 billion hours of viewership in its first four weeks.

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However, it wasn't always like this, at least in Harbour's mind. During a recent appearance on BBC's The One Show, the actor recalled how he thought the sci-fi horror drama would turn out to be a failure while filming season 1. "I remember when we were shooting the first season. We were down in Atlanta. Netflix had given us a budget of about $20," he said. "Halfway through, I remember my hair person coming up to me, like about episode four we were shooting, and she was like, ‘I don’t think it’s gonna work.'"

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Harbour continued, revealing that he didn't even think Stranger Things would land a second season at the time. "By the time we finished, we wrapped, I thought we wouldn’t get a second season we’d be the first Netflix show kind of ever to never get a second season," he added. "We thought no one would watch it, it was going to be a disaster."

Fortunately, time proved the actor wrong and the series eventually became one of the most successful Netflix products of the last few years. It also earned critical acclaim and numerous accolades for its acting, writing, visual effects, and more. Most recently, the fourth season of Stranger Things scored 13 nominations at the 74th Emmy Awards, including one for Outstanding Drama Series.

Earlier this year, series creators Matt and Ross Duffer announced the show would end after Stranger Things season 5, which will begin writing in August and is expected to hit the small screen in 2024. Although plot information remains under wraps, the season 4 finale suggested that Vecna is still out there (as Will sensed him in the ending scene), so he will likely return for one final battle.

Stranger Things seasons 1-4 are now available on Netflix.

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Source: BBC's The One Show