Andrew Scott and Paul Mescal discuss their onscreen romance in All of Us Strangers

It feels like Andrew Scott and Paul Mescal are lifelong friends, even though they insist their bond formed while working together on All of Us Strangers, the new drama from Looking and Weekend filmmaker Andrew Haigh.

On a Friday afternoon in Los Angeles in November, the pair remain in their own world. A cacophony of publicists and camera operators swirl around them, in the thick of a string of media interviews, but Scott, 47, and Mescal, 27, sit calmly shoulder-to-shoulder in a press room having their own private, whispered conversation. It's difficult to make out, which only makes you want to know what they're saying that much more. And when you pry, they shrug it off.

Perhaps this was what Haigh was talking about when he said, during an awards-season Q&A for the American Film Institute, that the three of them went to a concert in London together and his actors "completely ignored" him most of the day. "We didn't!" Scott insists. "That's not true," Mescal adds, laughing. "That's a little bit of hyperbolic directorial license," Scott says. "We need to have a word with him."

It's no wonder the internet has fallen for the bond between these Irish gents, fawning over photos of Mescal attending Scott's birthday party at a club. The pals say they only knew of each other "a little bit" prior to All of Us Strangers, but "not as well as we know each other now," Scott quips — alluding to the sex scenes they shot together for the movie. "We know everything. The whole kit and caboodle!" However, once people see the film — part romance, part ghost story — it's their emotional bond they forge on screen that stands out... and often leads to overt sobs from the audience.

Scott stars as Adam, a lonely screenwriter living in a near-empty apartment complex in London. He has a chance meeting with one of his only neighbors, a man named Harry (Mescal). The romantic relationship they form not only gives them both a connection they so desperately crave, but it coincides with an unexplainable phenomenon Adam is experiencing. While visiting his childhood home, he sees his parents (Claire Foy and Jamie Bell), who appear as the same age they were when they died decades earlier in a tragic car accident. The film becomes a cathartic story about things left unsaid, finding life after trauma, and the pursuit of love (both familial and romantic).

On a personal level, Haigh, sitting with EW and his producer Graham Broadbent in the lounge at New York City's Mandarin Oriental hotel in October, says writing and directing All of Us Strangers proved to be a cathartic experience. The scenes where Adam converses with the ghosts of his parents in the house where he grew up were shot in Haigh's actual childhood home, a place he hadn't visited since he was 8 years old. "It was an emotional thing to make," the British filmmaker, 50, continues. "There were lots of very personal things in it for me. But it also was for Andrew, Paul, Claire, and Jamie. They all brought their own personal life to the table when we were making the story."

Scott and Mescal joke how it was their Irish heritage that helped them understand what Haigh was going for. "The means to express is something that we as a culture are still processing," Mescal says. "I think that's why Irish actors, generally speaking, are good at playing the stuff beneath the surface. A good healthy dose of repression helps the ol' acting."

The connection these actors forge through performance is palpable. It was a surprise even to them how affected the audience became when they attended their first public screening of All of Us Strangers in Los Angeles earlier in the week. "I was balling," Scott recalls. "We had to do a Q&A afterwards. I was really emotional."

The way Haigh filmed the sex is itself a reflection of the broader intimacy he was looking to achieve. "I wanted to express the feeling of connection and how you feel when you are with someone," he explains. "It's about where you're looking. It's about being vulnerable and then allowing yourself to feel a bit freer and then tense up and be nervous and awkward and then let the sexuality of it override you. It's all of those things. Sex is complicated, whether it's the first time with someone or whether it's in a longterm relationship."

"To play being in love or falling in love with someone, it's the best, completely wonderful thing to be able to do," Scott says. "We were starting to get to know each other [as people], as well. Beyond our preliminary friendship, it was like both of those experiences were coexisting."

All of Us Strangers opens in theaters Dec. 22.

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