'My Best Friend's Exorcism' cast found real connections that drive serious horror

When your film has a title like My Best Friend's Exorcism, the phrase "best friend" has a lot of heavy lifting to do. Yes, the new film from director Damon Thomas, based on Grady Hendrix's acclaimed novel of the same name, is a horror story at its core, but the terror only works if you really believe the friendships surrounding the scares. 

Luckily for stars Elsie Fisher and Amiah Miller, that was never an issue.

"I think we really just hit it off pretty immediately in real life, and the rest sort of filled itself in," Fisher told SYFY WIRE ahead of the film's premiere earlier this week. "We didn't shoot everything chronologically necessarily, but we kind of started with mostly the more normal chunks [of the film] at school or driving together. And then we did a lot of the exorcism stuff. So it was sort of a natural progression, and then if we had an emotional scene, I feel like that only brought us closer together."

Miller added, "We were very lucky, and I was actually kind of nervous, because I can always tell when I watch something and I'm like, 'They don't like each other, or they just don't connect.' But I met [Fisher] and I was like, 'Oh yeah, we're going to be besties in real life whether she likes it or not.'

Fisher and Miller play Abby and Gretchen, respectively, two best friends attending the same private school in the 1980s, whose friendship is pushed to its limits after a strange encounter leaves Gretchen possessed by some dark force. The consequences of this possession soon spread, enveloping not just Abby and Gretchen's lives, but the lives of their other best friends Margaret (Rachel Ogechi Kanu) and Glee (Cathy Ang), eventually leaving Abby with no other option but to turn to an inexperienced exorcist (Christopher Lowell) for help. 

As in Hendrix's novel, what follows is a blend of all-out horror and teen comedy that centers on the story of four girls all trying to deal with a sudden, dramatic change in their lives. For Thomas, that meant casting his four leads with the right chemistry was crucial. 

"We started with Elsie Fisher whom we all loved from the movie Eighth Grade," Thomas said. "We thought that she would be the perfect Abby. We then wanted to find the perfect Gretchen. I looked at an enormous amount of self-tapes. I whittled it down to three potentials. We then did chemistry reads with Elsie. Amiah and Elsie just seemed to click and they so felt right acting together. Once we had our Abby and Gretchen we just need to find our Margaret and Glee. Rachel and Cathy seemed to be so right too. They both gave the quartet a good balance of personality types."

To adapt the novel, the production turned to Jenna Lamia, an actress, and screenwriter whose major scripting credits so far include the TV series Awkward and Good Girls. For Hendrix, whose other books include The Southern Book Club's Guide to Slaying Vampires and The Final Girl Support Group, the key to adapting his book was not capturing every single story detail, but getting certain essentials of the characters right in a way that reflected the challenges of high school life.

"As long as it's about two girls whose friendship is strong enough to beat Satan, you can do anything to this story and it still works," Hendrix said. "But, it's always nice to see people staying true to certain details, and in this case, I really appreciate that poor Elsie Fisher was convinced to play yet another character with bad skin. I had terrible acne in high school, and I think it's tough as a kid to go out in public every day feeling like a monster-faced pus factory. It really shapes how you talk to people, how you walk, how you stand, how you exist - you basically just want to be invisible all the time. You rarely see bad skin in movies treated as anything but a punch line so it's nice to see that they cared enough to give that source of adolescent shame some respect."

Indeed, one of the key narrative drivers of My Best Friend's Exorcism, as Gretchen's possession saga wears on, is the realization that each of the four main characters is dealing with some kind of personal demon, be it self-consciousness about their skin, their love life, or some other, darker force.

"All four of us got to have our own mini-movie," Kanu said. "We were all the main characters to ourselves. And [with] Margaret's sort of progression throughout the film, there are sort of hints dropped as to what her inner demon is going to be. And then it becomes a big demon in her life, not an actual demon, but you'll see."

But demons aside, to pull off the delicate balance of all these characters who are, in the end, also just trying to get through high school, My Best Friend's Exorcism also had to infuse its narrative with a healthy dose of comedy. The scares and the laughs are very close together in the film, often in the span of the same scene, and for the cast, that was always part of the formula.

"I think you would imagine that there would be a lot more of a struggle, but ultimately, I find a lot of horror films to be funny," Fisher, whose previous credits also include this year's Texas Chainsaw Massacre, said. "So it was actually just very cathartic to be able to play into that and maybe really push a facial expression. A lot of it is also [playing] the scenes very straight, and just the way they're structured and written ends up sort infusing all these different elements."

"I think it was very important because the story is about, in my opinion, what happens when a friendship breaks, or when you don't hold onto each other," Ang said. "And I think seeing that unfold, it's a roller coaster of emotions, so it should be scary and funny and heartbreaking. And you feel so much as a teen growing up and going through these struggles in your friendships all the time, and so I felt like the fact that it explored the whole spectrum of emotions was just natural."

My Best Friend's Exorcism is now streaming on Amazon Prime Video.

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