Backstage with... The Wretched: The low-budget horror unexpectedly breaking box office records

There's no doubt the film industry has been hit hard by the coronavirus outbreak, but away from the production shut-downs and postponed release dates one unlikely movie has been having its Hollywood moment.

Low-budget indie horror The Wretched has become one of just five films in more than 20 years to top the US box office for five weeks - the others being Titanic, Avatar, The Sixth Sense and Black Panther, to put it into context.

While it sounds like an impressive achievement, it has to be said that due to the COVID-19 lockdown there's not exactly a lot of competition out there at the moment, with most studios choosing to hold their films back or release them straight to on demand.

But indie company IFC Films has bucked that trend by sticking to its release schedule and rolling out films as planned at the few movie-going venues that are still open for business - mainly drive-in theatres.

The Wretched's writers and directors, brothers Drew and Brett Pierce, admit they never expected their horror to have the impact it has.

"It felt like a joke at first," Drew told Sky News' Backstage podcast.

"We had our first week and we only opened up in 12 theatres, but we'd done really well… and then they obviously rolled out into more theatres and we thought it might die off, but the audience I think embraced the movie and loved the movie so much that word of mouth spread, coupled with obviously how weird times are and that drive-ins are sort of this great escape, and it just kept growing.

"It's been like this snowball rolling downhill, you know... We were shocked at first and now it's just so exciting."

Brett says it has been hard to get his head around the film's reach during lockdown.

"It's weird because we're locked up in our apartments and it's just like we keep hearing all of this stuff and seeing it online, and then part of it doesn't feel like it's actually happening because we're cooped up," he said. "But I guess there is an outside world that's moving forward."

The Wretched, which is available on Sky Store, tells the story of a teenager, struggling with his parents' divorce, who takes on a 1,000-year-old witch posing as the woman next door.

It pays homage to classics of the genre including Fright Night and Rear Window, and the brothers may have always been fated to have successful careers in horror, as their father, Bart Pierce, created the special effects on cult classic The Evil Dead.

Drew says growing up around film-makers definitely influenced the siblings.

"We witnessed our dad making shorts with [Evil Dead director] Sam Raimi and that whole crew on and off as we grew up, even past Evil Dead.

"They were shooting these little stop-motion shorts and stuff outside in the back yard and we'd be around, so film-making is sort of part of life. I think most people see it as sort of this untouchable thing, but I mean, the truth is we kind of embraced that.

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"Like even our movie, The Wretched, and our previous movie Deadheads, our mom did the craft service, we put everybody to work. Our dad, who was the special effects guy, he's like our super PA, we send him on runs and he picks up actors."

Here in the UK, we don't tend to have space for drive-in theatres and the film has gone straight to on demand, but some other countries are now attempting to emulate the US's drive-in effect.

Brett says despite the film's release in such specialised theatres being something of an experiment, it was ultimately a blessing in disguise.

"We were like, of course it makes sense we're not going to be in theatres because of the pandemic and we're okay with it. We're disappointed as film-makers but realise it's just not possible.

"And I think even IFC was putting their toes in the water, like we're going to try it at a couple of drive-ins where we think people might like this movie, and it just took over."

The Wretched is available to rent in the UK from Sky Store, iTunes & Prime Video.

Hear more from the interview and a review of the film on this week's episode of Backstage - Sky News' entertainment podcast.