Sierra McCormick spent a lot of time off-set getting her character in The Vast Of Night just right. Set across one fateful night in 1950s New Mexico, the American actress (22) plays a young, winsome switchboard operator named Fay in the new sci-fi thriller.
And she actually had the switchboard moved into her hotel room every night after rehearsal and shooting, so she could practise using it - "just plugging it in, releasing, plugging it in" - for a couple of hours at a time.
"It's one of those oddly satisfying things," suggests the North Carolina-born star, who first became known for participating in the game show Are You Smarter Than A 5th Grader?
"The switchboard is a huge asset to Fay's character that I wanted to explore, because one, it's her job and two, it ties in with this whole technology aspect that she's really excited about and really loves.
"There's a lot of YouTube footage, actually, of women from that time period operating switchboards, and I noticed this very swift flick of the wrist motion they had to plug the things in, because they do it all the time. So, I was like, 'I need to get that'!"
The film - directed by Andrew Patterson (his debut feature), and written by James Montague and Craig W Sanger - is photographed in soft, inky-dark tones and shot in nearly real time.
It follows Fay and charismatic radio DJ Everett (Jake Horowitz) as they discover a strange audio frequency that could change their small town and the future forever.
Asked how she related to Fay, McCormick notes: "I started with her sort of just most general inward qualities, what makes Fay Fay, regardless of time and place and everything like that. And what really drew me to her initially is that she reminds me a lot of my younger sister.
"If you ask Jake or Andrew, they'd probably agree that, in real life, I'm not very close to Fay a whole lot - but my sister is. She is just this very sweet, optimistic... She believes everyone is good and has the most hope and stuff for the future and the world.
"I'm not always that way, and I always admired that about my sister, and I wanted to explore that more in Fay as well."
The Vast Of Night has a very distinct style, both visually and in its dialogue.
McCormick - who has also starred in TV shows such as Supernatural and Disney Channel's A.N.T Farm - agrees that, at times, the feature feels like it could work as a radio play, which she says was Andrew's influence.
"He wanted it to feel like you were settling in for a radio play," she elaborates.
"And actually, when I went and saw the film in a drive-in here in southern California, the audio actually comes through over your car radio when you go and you watch it.
"And so, it was this incredible other dimension for the film, because you were actually sitting in and listening to this story, as they are in the movie, like through the radio."
The film is certainly a twisty watch, falling down the rabbit hole of Rod Serling's The Twilight Zone, the ground-breaking American anthology series in which people try to solve their problems using their own unique ideas.
As the story progresses, we follow a scavenger hunt involving dropped phone calls, AM radio signals, secret reels of tape forgotten in a library, switchboards, crossed patchlines and an anonymous phone call.
What does McCormick think The Twilight Zone style adds to the film?
"I think it adds this sort of expectation you have going in because I feel like those kinds of shows, and those kinds of movies, you have an idea about how they're going to play out; you've seen a lot of them before, they've been done many, many, many times.
"And then the film does the opposite. It does all these really interesting, very different stylistic choices with this idea, this genre that's been touched on a lot.
"And I think that was a really smart thing to do."
The movie is about something unknown and unquantifiable; it's chilling and scary, even though it's not specific about what we should be frightened of.
At a time when we are living through the Covid-19 pandemic - an unprecedented, uncertain and fearful time - perhaps the themes feel particularly relevant.
Even though McCormick comments that usually "horror-wise, nothing scares me", she found that wasn't the case watching this project back.
"There's a moment in this movie and even though I lived it, I shot it, I've seen this movie 20 times, it never fails to send a shiver, just because there is this major fear."
She continues avidly: "2001: A Space Odyssey, when I saw that when I was a kid, it wasn't very scary, it didn't really scare me... When I saw it when I was an adult, I was like, 'That's the scariest movie ever, that movie is terrifying, how did I not notice it was so scary'?
"As you get older, the unknown becomes more and more of this thing that you think about, and this movie kind of touches on that, I think."
With cinemas a no-go in lockdown, she hopes people watching on Amazon Prime at home have "the lights off and the sound up".
"That's the best way to view the film," she enthuses.
"The film conjures up nostalgia. And it has all these varying layers of stuff; all these very light, sweet moments and these comedic moments and these big moments and then these really eerie moments. And I think a film that takes you on a journey like that, is really a good thing when you're trying to escape the current situation.
"I feel like this movie might be a good respite for people - at least I hope it might be."
The Vast Of Night is available to stream on Amazon Prime now