It's part comedy, part tragedy. It's part road trip saga, part odd couple film, and part Holocaust film. What could possibly have gone wrong?

Yes, anything could have gone wrong. So the first miracle “A real pain” Writer-director Jesse Eisenberg's remarkably accomplished film about unlikely cousins ​​on a dark journey through Poland manages the most delicate balancing act.

It is all the more impressive that at the same time interesting questions are asked about the nature of pain – personal vs. universal, historical vs. contemporary. As is the fact that it's an Oscar-worthy performance.

This stunning performance comes from Kieran Culkin, and what's noticeable is that she doesn't overwhelm the rest of the ensemble. Above all, this is a testament to the careful way in which Eisenberg, who stars in the less flashy role, constructed and paced his film. As for Culkin, if you needed proof that his stirring, Emmy-winning work as the tormented Roman Roy in Succession wasn't a fluke, here's it.

The film that is only Eisenberg's second directorial effortcomes from a trip the “Social Network” star took to Poland around 20 years ago. There he found the tiny house where his aunt had lived before the Holocaust uprooted the family. He wondered what his own life would have been like if World War II had never happened.

And that's one of the many conversations David (Eisenberg) and Benji (Culkin) have as they travel through Poland to visit the house where their recently deceased grandmother once lived. (Eisenberg used the exact same house, which shows how personal this film was to him.)

It's a poignant but awkward reunion for the cousins, who were close as teenagers but are on very different paths as adults in their 40s. David is the anxiety-ridden but high-functioning type that actor Eisenberg excels at. He works in technology and lives in Brooklyn with his wife and young son. Benji lives in the north of the country and is largely undeveloped or undeveloped. He's also an expert in contrast – the type, as David notes, who can light up a room when he walks into it and then insult everyone. The death of her grandmother, with whom Benji was close, has taken a toll on his mental health.

The cousins ​​first meet at the airport in New York. Before they even get through security, Benji terrifies David by telling him that he's secured some really good weed for the trip. (Don't worry, he sent it to the hotel.)

In Warsaw they meet their small tour group and the British tour guide James (Will Sharpe from “The White Lotus”), a scholar about wartime Poland. Fellow travelers include Marsha (Jennifer Grey), a divorcee who has moved back east from LA and is trying to reconnect with her past; a Midwestern couple (Daniel Oreskes and Liza Sadovy); and Eloge (Kurt Egyiawan), a Rwandan-Canadian convert to Judaism who knows something about genocide.

Before long, Benji charms and annoys the group – and this turbulent brand of charisma is Culkin's specialty.

He runs towards a war memorial statue to strike a playful action pose, embarrassing David. But somehow the whole group joins Benji in the childish stunt and David has to take photos.

As the tour participants then board a train to Lublin, Benji suddenly erupts in anger at the group – how can they sit in first-class comfort when their ancestors were crammed into cattle cars 80 years ago? He disappears in a lower class car.

And while visiting a war gravestone, Benji angrily admonishes the mild-mannered leader for focusing on statistics and not letting the group feel the pure emotions of the moment. (He's not wrong, as the Führer will later confirm.)

Eisenberg said that when he was conceiving his film, he noticed a Polish ad that promised “Holocaust tours (with lunch).” All of these moments felt quite real; Indeed, such tours are full of uncomfortable (and rather unavoidable) juxtapositions of modern tourist comforts and historical horrors.

Speaking of horror, by far the most difficult scenes occur when the group visits Majdanek, the Nazi camp. There they pass unspeakable sights of gas chambers and ovens and piles of abandoned shoes. At first you might be surprised that Eisenberg even brings us here; He wisely hides these moments. When Benji collapses, he is on his way home – a realization that such reactions often come later.

At the end, as the cousins ​​uneasily hugged each other goodbye at the same airport where we started, having endured a journey both physical and personal, it's hard not to think of the film's title. Yes, Benji is “a real pain.” But there are layers of pain at play here, too.

There is David's very real pain, a fear that forces him to take pills every day. There is Benji's pain, which not long ago sent him into a very dangerous downward spiral.

But Eisenberg seems to be asking how “valid” this kind of pain is compared to the historical pain the film explores in Poland – a place where, as his camera shows empty streets that once teemed with life, a entire people were wiped out by the Nazis?

It's quite a journey for a film. We thank Eisenberg and his amazing co-star for making the road trip so thought-provoking.

“A Real Pain,” a Searchlight Pictures release, is rated R by the Motion Picture Association “for language throughout and some drug use.” “Running time: 90 minutes. Three out of four stars.