51����Ƶ

“You never quite know what’s gonna come out of him and I didn’t want to plan that ahead of time,” he says.

In “A Real Pain,” he’s the cousin who’s untethered, outspoken and, often, a real pain to his more structured relative, played by Jesse Eisenberg. The stance rankles, of course, but that’s part of their journey. The two are on a trip to Poland where they hope to honor their late grandmother. Unfortunately, the two haven’t been in much contact and live wildly different lives.

Eisenberg, who also wrote and directed the film, is a lot like his character, David. Ditto: Culkin and his Benji.

High anxiety

At one point during filming, Eisenberg came to his co-star and admitted “he was having a lot of anxiety about me. And I was like, ‘Trust me. When we get there, I’ll know the words. I can look at it literally on the walk to the set. I’ve read it. It’s in the back of my brain somewhere. It’s fine. I got it.’ And that gave him more anxiety.”

While Eisenberg considered playing Culkin’s role, he was quickly talked out of it by producer Emma Stone because “he’s so right for David.”

Still, that didn’t ease the director’s mind. When the two talked about the stress, Eisenberg asked Culkin, “Did you think you and I were going to be alike?”

And Culkin said, “God no.” And Eisenberg said, “I did.”

“That was a big one for him,” the “Succession” star says. “He thought: similar actors, similar age. We talk fast. Same sensibility. We’ll have the same approach. But when his anxieties went through the roof, (mine) didn’t. I got to rely on a great script and just say the words.”

Attention paid

The on-screen friction is making “A Real Pain” an early candidate for awards attention. Culkin’s free-wheeling approach has him in the hunt for a Best Supporting Actor Oscar.

Even though he won an Emmy for the last season of “Succession,” the 42-year-old father of two wasn’t interested in following up the series’ run with a movie. Rest, in fact, was paramount. “A Real Pain,” however, got pushed up and he was quickly on a plane to Poland. He thought about bringing his wife and children on the shoot but “kids being like 1 and 3 would’ve been a nightmare for all of them,” Culkin says. He faced the work alone and realized, “It was really, really hard but I’m very, very, very glad I got to do the movie.”

Because Culkin was familiar with Eisenberg’s work, he was sure he’d be in good hands. “All I gotta do is take this brilliant writing and just do it with this guy who happens to be a good, competent actor who obviously understands the scenes because he wrote them.”

Eisenberg, he says, turned out to be a fantastic director who was very inclusive. “I knew I had a voice when it came to my character, but he also was willing to hear my opinion about other things. He wants to know what people think …. he’s curious. It felt like we were all making this film.”

Just like...

When Culkin got to see the finished product at the Sundance Film Festival, his wife leaned over and said the name of a friend – someone who could have been a reference for Benji. “And I went, ‘You’re totally right.’ That must have been on my mind. I just sort of compartmentalized it and tucked it away somewhere.”

What appealed to the actor was the character’s spontaneity. "Just when you feel like you’ve got a sense of who this guy is…he says something completely different, and it can be read at many different temperatures.”

While Eisenberg thought he might be able to play Benji, Culkin knows he couldn’t have played David. “I couldn’t sit in my skin and feel comfortable as David,” he says. “I don’t think I would watch that movie simply for my performance as David being boring as hell.”

Now, Culkin says, he can see David and Benji as kids. “I know where they came from and how they’ve gotten this way, which says something huge about the writing.”

"A Real Pain" opens throughout the country in November.