Reece Shearsmith on new film In the Earth, not writing any lockdown Inside No.9 episodes and why Carry On Camping is a folk horror

In the Earth – Shearsmith's third collaboration with writer/director Ben Wheatley – leans more towards horror than comedy. But as with his previous films, Wheatley has used many performers notable for their comic output, with Shearsmith and Plebs star Joel Fry taking on leading roles. And Shearsmith says that actors with a comedy background are often perfect for this type of film, in part because the two genres demand such a similar skill set.

"I think Ben knows full well that it's really hard to do comedy, but it's great when you get comedic actors in scary situations because I think they can give you it all," he explains. "And Joel was brilliant, a brilliantly low-key performance of absolute terror and being out of your depth in this film. And I think that was one of the relentlessly blackly comic things about his journey."

As with A Field in England, one of Shearmith's previous collaborations with Wheatley, In the Earth falls into the sub-genre that's come to be known as folk horror – a term popularised by his League of Gentlemen colleague Mark Gatiss in the 2010 BBC documentary A History of Horror. The two films make for interesting companion pieces – and Shearsmith says that in a previous iteration of the script they were even more closely linked, with his characters in each movie originally sharing a surname, suggesting a shared ancestral lineage. But what actually makes something a folk horror?

"Folk horror as a term is quite new, but there's certainly an interest in it," says Shearsmith. "It's the mundane and it's the earthiness and the unknowableness of something bigger. That's the scary thing about folk horror. And you know, I think Carry On Camping is folk horror in its own way because it's got that sort of strange sort of grimness about it, and it's outdoors, and its's hard.

"You know, there are lots of versions of what folk horror is. Another great one that we've cited in the past is Blood on Satan's Claw, which is another film that feels like it's filmed in the 17th century, such a great look, and the English countryside is so beautiful in it as with Witchfinder General. So there's a real lineage of fantastic ones that I really enjoy as films, and it's been nice to be in two of them, two modern ones in a way."

Besides genre, another thing that makes the movie interesting is that it falls into the newly created category of 'pandemic films' – sitting alongside recent movies including Host and Locked Down as one that was conceived, written, shot, and now released in the midst of the pandemic. The film itself takes place during a pandemic as well (although it's not specifically stated that it's the same one we're living through) and Shearsmith's character Zach, a rather crazed conspiracy theorist and possible murderer, takes rather an unusual approach to the catastrophe – decamping to the woods and performing a series of bizarre rituals.

As Shearsmith puts it, "Zach has become increasingly wrapped up in a version of events and a narrative that he's constructed for himself that sorts everything out... And it might not be the truth, but it's the truth to him." That mindset certainly sounds familiar, and I ask him if he thinks there are parallels between Zach and some of the real-life conspiracy theorists who have sprung up during lockdown.

"I think that Zach would certainly buy into such things," he responds. "Yeah, he would be definitely thinking about there's something in the 5G thing, and there is a bigger, bigger picture.

"But he sort of represents the side of man that's more spiritual, and I think a bit more supernatural in a way... that you'll be repaid because of your ardour to this sort of unknown, unknowable bigger entity, and that's the woods and that represents a lot of people's blind faith and comfort in religion.

"And then in the film, we have another character that's the science version of that. It's a different route, but it's sort of the same thing. And that was what Ben wanted to explore, I think, which is interesting for the film because he takes it into different fields tonally, it goes into various different types of film.

"My bit of the film is sort of body horror/slasher/scary man/Texas Chainsaw bit, then we get a Quatermass/Doctor Who section that becomes very to do with the science of it and explains it in a completely completely different way, in a rational way, that's actually still as mad."

Shearsmith says when he first heard about the film at the beginning of lockdown and asked Wheatley if there was a role for him, it was more out of hope than expectation – believing that they were still a long way from film and TV being able to go back into production. But in reality, the whole thing came together quite easily, and he says that filming last summer felt like a "ray of hope", especially given how safe everything seemed.

"I was thinking, at the beginning, we won't do it," he says. "This is nice for him to be writing something, you know, but I can't quite believe that we'd even get it together to do anything. We won't be allowed to do anything. So I didn't really give it much thought.

"And then suddenly the dates were set in August, and we were going to start having COVID tests and it was all like a real production was underway. And he managed to do it incredibly, you know, I think we were one of the first people to creep out into the world and film something!"

So, given his experiences on this film, has Shearsmith thought of writing anything set during the pandemic himself? He says the idea crossed his and Steve Pemberton's minds when crafting the sixth season of Inside No.9, which recently concluded on BBC Two, but they ultimately decided against it, anxious that it could come across a little gimmicky and overplayed.

"We did think about it, and then we very quickly jettisoned it because we thought there's going to be loads of them," he said. "And we wanted to be a bit timeless and not be 'Oh, that's that episode where it was in the pandemic'.

"So we very quickly thought, let's not do that, and let's just stick to telling stories that are not of any time particularly. And also, let's not hold up a mirror to yet again, another Zoom call-based episode, you know. We could absolutely do it, it feels very suited to it, and I think people were expecting maybe in series six that there might be some lockdown episodes.

"But we, we sort of went the other way thinking it would be done to death by the time we did one. And we didn't want to be like just another one."

After six series, Inside No.9 continues to attract all sorts of praise, with the fifth season recently picking up a BAFTA for Best Scripted Comedy, and the most recent batch of six episodes being met with yet more critical acclaim. But Shearsmith says that despite all the accolades, the nature of the show means he remains nervous before each episode is broadcast.

"It's a real hold your breath time when they're going out because you've worked so hard on them," he says. "And what the No.9s do is they afford everyone six judgments.

"Because we always talk about how if it were just a series and it was the same thing each week, or it was a sitcom, you wouldn't in the same way rank the episodes of a six half-hour thing. It's because they're all individual films.

"You've got that thing where it's like, 'Oh, they're brilliant, they're back on form,' 'Oh, they're terrible, they've gone and lost it,' 'Oh, it's fantastic again,' and all it is is taste.

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"They're all good, there's nothing bad about any of them. We don't write the dud one, deliberately. We write all stories that we think are engaging, and some will hit because you liked it. The person watching it might respond more to the more psychological ones. Some people might like the silly ones. But that is the very nature of an anthology series where you don't have to like every one. But we creating it have to feel like we've given you six different chocolates."

Given the success of the recent episodes, here's to many more treats from Shearmith and co. in the future.

In the Earth is in cinemas from Friday 18th June 2021 and Inside No.9 is available on BBC iPlayer. Visit our Movies hub for all the latest news. Looking for something to watch tonight? Check out our TV Guide.