Kieran Culkin is no stranger to sassing his costars, but things got a bit more complicated while he was shooting his upcoming movie, A Real Pain.

This time around, his onscreen cousin in the film, played by Jesse Eisenberg, was pulling triple duty as its star, writer, and director.

While they shared the stage in Park City, Utah for the 2024 Sundance Film Festival, Culkin reflected on the experience of being directed by a fellow actor.

“That was a first for me," said the Emmy- and Golden Globe–winning Succession star. "And it felt like there was a pretty good rapport right away. But then right after the first scene, he’d be like, ‘Cut’ and start giving me notes. And my first thought was, like, ‘B----, I got notes for you, too.’”

As the room, including Eisenberg, erupted into laughter, Culkin jokingly added, “I don’t want to be noted by an actor. Get out of here. F--- you.”

Courtesy of Sundance Institute.

Eisenberg’s A Real Pain premiered at Sundance on Saturday. The movie follows two mismatched cousins (Culkin and Eisenberg) who reunite for a tour through Poland to honor their recently deceased grandmother, who survived a concentration camp before moving to America. It takes an emotional turn as the pair explore their family history, reignite old tensions, and come to terms with their present melancholy. A semi-autobiographical tale, the project involved shooting scenes at Eisenberg's actual grandmother's home.

Jokes aside, Eisenberg was quick to praise his costar when introducing him at the panel for the movie's Sundance screening. “I’ve never seen a greater performance in person, and maybe on screen, except, I don’t know, On the Waterfront, but I don’t even remember it that well,” Eisenberg said of Culkin’s work in the film.

As for his own feelings about balancing the job of both director and actor, Eisenberg said it was a “joy” with both positive and negative aspects.

“It’s good and bad, being in it, because you can have a little more control over the pacing,” Eisenberg explained. “On the other hand, it’s bad having a toe outside of my performance. Normally, when I’m acting in a movie I just give myself over to my character. I don’t think about the schedule, I don’t think about the shots, I don’t think about how I’m gonna look in the movie. I just kind of enjoy living in the circus of the thing and indulge in that.”

John Salangsang/Variety via Getty

He continued, “And then this, we’re editing the movie… and you just keep seeing me in the scene looking over to make sure the dolly’s in the right place. And so, my foot’s a little out of it. So maybe that’s the downside.”

He then concluded that Culkin played a significant a role in easing his experience as a performer in A Real Pain.

“Kieran has the part that is the most demanding part,” he said. “So the other trick that you do as an actor is, when you’re nervous on stage is when you put your energy and anxiety onto the other actor, and they do the same to you. “

The film also stars Dirty Dancing's Jennifer Grey and The White Lotus actor Will Sharpe. After its warm reception at Sundance, Searchlight Pictures acquired A Real Pain and plans to release it in theaters this year.

“Making A Real Pain was a true labor of love, and it has been so thrilling to premiere at Sundance," Eisenberg said in a statement. "I couldn’t be more honored to work with Searchlight and to bring this story to a wider audience.”

Additional reporting by Gerrad Hall.

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