'Midsommar' star Jack Reynor on filming the year's craziest sex scene

Warning: Minor Midsommar spoilers ahead.

"It's f--ked up, right?"

Jack Reynor asks the question in his Irish brogue with unadulterated glee, pride even, as he sits down for a cup of coffee on the back patio of a rustic West Hollywood eatery. He's referring to Midsommar, the new Ari Aster-directed mind-bender about a group of U.S. graduate students who head to the Swedish countryside to join one of their classmates for his extended family's "traditional" festivities celebrating the summer solstice.

If you saw last year's similarly unnerving arthouse horror hit Hereditary, which put Aster on the map with a couple exclamation points (and at least one decapitated head) after stunning audiences at Sundance 2018, you won't be surprised to hear that the Eurotrip turns into the stuff of twisted, sordid nightmares for Reynor and friends as their cultish hosts launch into increasingly violent pagan rituals.

"Pretty sure it was directed by Satan himself," a Texas journalist tweeted after the first film's screenings — a post Reynor happily shared on Instagram. "A mad descent into What-the-F**ksville."

Reynor, the talented 27-year-old actor best known for indie (and sometimes unfairly-under-the-radar) films like Glassland (2014), Sing Street (2016) and Kin (2018), plays Christian (the character's name itself likely a wink penned into the film's religious themes), a guy on the brink of breaking up with his girlfriend Dani (Florence Pugh) when she endures a devastating family tragedy. Christian then reluctantly invites Dani to join him and his bros Pelle (Vilhelm Blomgren), Mark (Will Poulter) and Josh (William Jackson Harper) on their jaunt.

The Colorado-born, County Wicklow, Ireland-raised Reynor was approached with Midsommar prior to Hereditary's buzzed-about Sundance bow. But as one who identifies as a cinephile (he even runs an Instagram movie club dedicated to classics and world cinema), he was immediately smitten not only with the script but Aster's impressive string of atmospheric shorts, which dabbled in both horror and dark comedy. "He uses a very elevated style of filmmaking to tell really f--ked up and really interesting — but really f--ked up — stuff that feels very much of today and contemporary," said Reynor, a champion of the F-bomb. The pair soon bonded over the works of British satirist Chris Morris (Four Lions, The Day Today) and filmmakers like Kenji Mizoguchi, Michael Powell and Emeric Pressberger (a.k.a. The Archers), Ingrid Bergman and Roy Anderson, all influences Aster tapped into for Midsommar.

Because there are 20-some hours of sunlight in midsummer Sweden, the film's scares are all pulled off sans darkness — or at least, darkness in a literal sense. "The whole idea that you would exhibit so much darkness in just blistering daylight for a whole film like that, it's an exceptional achievement," Reynor says. "I can't think of many films that do that, and certainly not that do it quite so well."

Despite the pictureseque environs of the film's rural Budapest set, the shoot was "hard going," Reynor declared. "There was a lot of waiting around in really hot direct sunlight. … But a film shouldn’t be easy to make. If you're making a film that's not challenging your or forcing you to interrogate your creative process a lot, then it's never gonna rise above mediocrity."

There were also the psychologically tormenting aspects of the plot and role, with his character gradually losing his sanity, which Reynor explained can weigh on an actor — and which he found a viable way to counter. "The entire film was an exercise in the practician of just peak mental health. So no drinking during the week whatsoever, at least eight hours sleep every night, cooking for myself, going to the gym, running 5K and doing a solid workout every day if possible. And I just kind of forced myself to do that no matter what," he said. "I've never been on a project before where I felt the need to maintain good mental health so much. That's the kind of movie that will f--k you up if you weren't looking after yourself."

That was particularly true when it came to one of the film's most shocking sequences — a lengthy sex scene that finds Reynor and a female character copulating as a dozen women of all adult ages surround them, fully nude, rooting them on in deranged fashion.

"I found the sex scene very difficult," Reynor admitted, "calling it "humiliating" and "exposing." The scene required the actor to do full-frontal nudity, a first for him.

"That kind of stuff has typically been reserved for females in cinema. And they've gone through that stuff again and again and again, in the slasher genre particularly, or Italian Giallo films, where it's just a really humiliating thing, and you don't see it happen to male actors so much. So it was really intense, and it was part of the reason why I wanted to do the film, because I wanted to experience that. And I definitely felt very vulnerable doing it. While being aware that there were also a dozen women in the room who were all completely naked, and they were also in a very vulnerable position."

The number of people undressed in the scene made that scene slightly easier for him, but it also heightened his awareness. And the experience stuck weighed on him for days. "I was conscious that there was like 12 or 13 women in the room all [doing] full-frontal nudity, and that there were probably 15 men in the room who were all fully clothed, and I was the only man in the room who was completely naked. There was a lot going through my head about it. I was more concerned about them than I was myself. But I was obviously feeling my own vulnerability fairly acutely," he explained. "It was really nerve-wracking, and definitely after I left, I got on a plane and came home to Ireland, there were a couple days where my brain was frazzled from it. So I can only imagine what the rest of those ladies who had been there that day were feeling."

It was well worth it, though, for Reynor — a continually up-and-coming actor and aspiring writer-director (he just helmed a period horror short, Bainne, starring Poulter that he wrote while filming Midsommar) who continues to draw praise for both his career choices and his performances. "I feel like although there might not as prominent of an awareness about me in the industry, I'm not spending my time doing things that I don't enjoy. ... I really feel like I've been really blessed to be able to support myself and sustain my lifestyle and not really compromise on exactly what kind of films I want to work on."

It's ironic, then, that Reynor's first major film role came in 2014's Transformers: Age of Extinction, the fourth entry in Michael Bay's robot-clash franchise that is wholly emblematic of the type of CGI-fueled Hollywood blockbuster that cinephiles like, well, Reynor, like to trash. And that is not the least bit lost on him.

"It was necessary, you know what I mean? I needed to do that in order to be seen for things like Glassland, Macbeth, Sing Street, Freefire. So I have no regrets about it doing it at all. And it was a helluva an experience. The traveling was pretty amazing, working in that environment, though yeah, you're gonna get some f--king PTSD from doing it. It was an eye opener. So I would never give back the experience, but yeah it hasn’t really been at the top of my priorities to do a big franchise or get into a series of franchise films since."

There was, however, one enormous franchise that Reynor almost enlisted in. In early 2016, just as Sing Street was set to open, Reynor was reported to be one of three finalists for the role of young Han Solo, which eventually went to Alden Ehrenreich in 2018's Solo: A Star Wars Story.

"I did go up for Solo, yeah," he said. "I would've loved to have done that. I grew up with Star Wars movies, I love Han Solo. I tested with [original directors Phil Lord and Chris Miller, who were eventually replaced by Ron Howard], thought they were great guys, great collaborators. It was a long process. But it was cool to be considered for that. That's one of the few things that I would have considered. Who's not going to consider that?

"I watched the movie when it came out and to be honest with you it was my favorite out of all the recent Star Wars movies. I thought Alden Ehrenreich did a f--king blinding job, you know? I thought he was really great in it. I thought it was really good."

The experience of coming so close to such an iconic role did not deter him, though, from big budget filmmaking.

"What's for you won't pass you by, you know what I mean? And to be honest with you I'd love to find a character that interests me that I can build that from the ground up and not be stepping into somebody else's shoes. I don’t have any interest in doing things that are remakes or reboots. There's so much of that s--t out there. And I'm really just interested in original material as much as I can get it."

Thus his hard-earned participation in Midsommar, one of the most original — and "f--ked up" — films you'll find in theaters this summer.

Midsommar is now playing.

Read more on Yahoo Entertainment:

• John Carney and cast on following 'Once' and 'Begin Again' with 'Sing Street'

• Very Important Conversations with the cast of 'Solo: A Star Wars Movie'

• The three Han Solo contenders In their most Han Solo-ish moments

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