Will Poulter has done many different genres since his debut as a child Stallone fan in Son of Rambow.

He was in the YA franchise The Maze Runner, the good old American comedy We're the Millers, historical dramas The Revenant and Detroit, and the groundbreaking non-linear sci-fi of Black Mirror's Bandersnatch. He hasn't quite done horror before, although The Little Stranger has light horrific touches, and he was slated to play Pennywise in It before director Cary Fukunaga dropped out.

Midsommar is Will Poulter's first official horror movie. He plays Mark, a grad school student excited to join his friends on a summer trip to the remote Swedish town of Harga. Mark must be the class clown, because he certainly chimes in with quips. Hoping for a summer of taking mushrooms with his friends and British visitors Connie (Ellora Torchia) and Simon (Archie Madekew), Mark isn't quite ready for what happens in Harga.

Midsommar is from Ari Aster, writer/director of Hereditary, so you can bet the traditions of Harga aren't just a summer flight of whimsy. Their deadly ceremonies are especially hard on Dani (Florence Pugh), who was just coming along with her boyfriend Christian (Jack Reynor) to get away from a family tragedy back home.

Poulter spoke with Popdust about the real roots of Mark's comic relief in Midsommar, which was actually filmed in Hungary to mimic Sweden's 24-hour summer days. Midsommar opens July 2.

Mark (Will Poulter) arrives in Harga with his friends Josh (William Jackson Harper), Dani (Florence Pugh) and Christian (Jack Reynor) Gabor Kotschy / A24

Will Poulter: I was just checking out the website. It's really cool.

Thank you, and I know you're on a schedule so I'll get right to it. Mark clearly has the best lines and the most laughs in Midsommar, but there's a lot more to him than comic relief, isn't there?

WP: I'd like to agree, only because I saw Mark as one of those characters; unfortunately, probably everyone knows a Mark or has interacted with a Mark. That sort of mean sense of humor actually speaks to a kind of internal insecurity and self-loathing. I think part of the reason Mark detracts so much from everything around him and other people around him is because he's insecure and not entirely confident in himself. So I thought that was interesting. It's probably fair to say he projects one thing and feels something very, very different inside.

I completely agree and I definitely know Marks. At the same time, does that comedy provide a misdirect from the horror, or even a release of tension?

WP: Yeah, that's interesting. Potentially, it's funny because I feel like he exists in a friendship group with people who are far more analytical and really just smarter, who all have an appreciation for culture variations far more than he does. So it's weird, because it kind of creates a sense of weakness. I think that his defenses are up from the beginning, and he's never going to assimilate to any of their practices or the Hargan way of life. He's just immediately dismissive of all of it, so that means that he's never really at risk of being lured in. At the same time, he's so busy not taking any of it seriously and laughing at it all, or making fun of it I should say, that he doesn't ever see that there is something more sinister going on. He just thinks it's all very, very weird, but weird in a kind of funny way as opposed to weird in a sinister way, if that makes sense. Potentially, it can contribute to a false sense of security for the audience, but I think that much of the experience is aligned with what Dani is going through.

Maybe don't eat what the Hargans are serving you. Photo by Merie Weismiller Wallace, Courtesy of A24

So how does Mark justify staying after it turns deadly? Christian (Jack Reynor) and Josh (William Jackson Harper) are staying for their thesis, but what makes Mark stay?

WP: Well, after Connie and Simon, the story that they are encouraged to believe by the Hargans is that Connie and Simon left. I think Mark genuinely lacks the level of perception or observation to be able to ever really bring that into question. I think he just sort of buys that. That's also because I think, in my mind, Mark always thought the Brits were a little bit weird. Obviously, that's kind of fun to play in a sense because I know British people can be weird or what the British idiosyncrasies are that might lead an American person to think that a Brit is odd. So in my mind, Mark always thought Connie and Simon were a bit weird. When Connie and Simon left, he didn't question that. So really, it doesn't turn deadly before it turns deadly for Mark in my mind.

I know you've turned down horror movies like It in the past, that director Andy Muschietti said you disengaged from playing a dark and terrifying character. Did you find during Midsommar you had to stay in a dark psychological place for months?

WP: Respectfully, my reasoning for not doing It wasn't necessarily solely because of the psychological impact it might have on me. I think that was certainly a consideration in whether I was going to do it or not. But, I think playing a character who didn't really allow for the, as I say, sinister elements of what you see on screen to permeate through his consciousness and just remain a detractor of it all meant that I didn't necessarily have to go to a dark place with this one. Certainly, watching the movie, I appreciate how dark it is and also how dark it was at times for many of my co-actors.

I think the darkest thing that I explored with Mark is this idea of being a really self-loathing and insecure individual and that manifesting itself as mean jokes and detracting comments [about] the people around you. There's something very dark about that to me and also something very real and authentic. I think that's due to the strength of Ari's work as a writer/director. Everything that is disturbing and sinister on screen has a very real, organic, and/or human explanation. A lot of the terrible things you see in this movie are motivated by human instincts. There are no real science fictional elements. Even when things get really trippy and seemingly science-fictional, it can be explained by the fact that mushrooms have been taken or certain herbs have been ingested or one's own mind has turned on them. The really cool thing about this film is that authenticity runs through it like veins.

Was it really light out all night?

WP: Because we were in Hungary, it wasn't quite, but I went to Sweden this time last year for midsummer to research the project. It was sunny for about 19, 20 hours of the day which is kind of crazy and unique, unlike anything I'd ever experienced before. I've actually been to Iceland and experienced pretty extreme levels of daylight, but this is the most I'd ever experienced. It was good to get a sense of what a real midsummer tradition is like.

PD: Was the dinner scene very carefully choreographed so everyone sits down and picks up their forks on cue?

WP: Oh yeah. I think that shot alone or that setup rather took several hours. It was a long day trying to get that right.

Dinner in Harga Photo by Merie Weismiller Wallace, Courtesy of A24

Did you stay in an American accent on Midsommar like you have for other films?

WP: Oh man, you are so well-researched. That's amazing that you know that. Yeah, I did on this. I didn't when I came back to the hotel or whatever, but when I was on set I did. It's just one less thing for me to have to think about. I find [when] transitioning out of my natural accent into the American accent, I'm liable to make mistakes in transition. It's just one of those things that makes it easier for me. Then I think being around other American voices, like William Jackson Harper's for example, it just helps me improve my own. And obviously other members of the crew, like Ari himself. When it came to being off set, I dropped it because it's one of those accents now that I hope I'm growing more comfortable with. Whereas, if it had been a more challenging accent like, say, an Irish accent, which is what I did when I did Glassland with Jack Reynor, actually, I [find] myself having to stay in it the whole time just because it was so challenging. I couldn't really afford to go back into my English accent and risk slipping up when it came to trying to change back into the Irish one.