Dominik Bindl/Getty Images; Vivien Killilea/Getty Images Justin Long; Kate Bosworth
"We've been doing a horror movie every night for October, leading up to Halloween," Long, 44, tells PEOPLE. "So we've done Don't Look Now and The Exorcist and classics."
In fact, the couple, who were first linked in March before going Instagram official in May, have been relying on movie picks from their Barbarian director Zach Cregger. (Bosworth, 39, has a small but memorable cameo in the film, which is now available to stream on HBO Max.)
"We love what Zach did with this movie and his taste," explains Long. "And so we are now really trusting his taste in horror movies. He tweeted a list of movies, so we've seen Saint Maud and Audition, a bunch of movies that were on his list ... The Evil Dead. Tonight is Nightmare on Elm Street!"
"We just love horror," he says. "It's really limitless, what you can do with that genre. I think that's what we really have been enjoying about it."
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With Barbarian now available to stream and purchase, Long has been dubbed a "scream queen" by fans on Twitter for his memorable performances in a number of horror films over the years, including Jeepers Creepers (2001) and Tusk (2014).
"Yeah, I just saw that," he confesses. "It's so flattering. I just watched Halloween Ends and there's no more legendary a scream queen than Jamie Lee Curtis. To be up in that category is very flattering."
"As an audience member, I love horror movies," the actor adds. "So maybe subconsciously I gravitate toward them because of that."
In the case of Barbarian, Long tells PEOPLE it all came down to how his character, an actor facing serious allegations, was written.
"It was exciting," he says. "It was a real opportunity to play somebody pretty despicable and who was very flawed. And to find the humanity in that person, without justifying what they've done. That that person exists in the world, and that person has ways of justifying their behavior and ways of living with themselves."
Long adds, "I thought it was really smart, enlightened writing. I think it's important to be able to identify those people in life, but also in our art, I guess."
Barbarian is now available to stream on HBO Max and to rent and purchase on digital.