By Bob Grimm

Kieran Culkin goes next-level brilliant in A Real Pain, the sophomore directorial effort from Jesse Eisenberg, who also wrote the amazing script.

This is, in essence, a road movie, but it doesn’t have the usual funny interludes of touristy shenanigans. Culkin and Eisenberg play Benji and David, two anxious cousins traveling to their grandmother’s birthplace in Poland. Their grandmother survived the Holocaust, and their trip involves a tour through Holocaust sites, including a concentration camp, Majdanek. (This is believed to be the first time a narrative movie was allowed to film inside a real concentration camp.)

Benji is a live wire, constantly combatting hyper-anxiety with unbridled humor and all-too-brutal honesty. This renders him hilariously awesome, unpredictably nasty and unhinged, all at once. Other folks on the tour (including tourists played by Jennifer Grey and Kurt Egyiawan) are simultaneously enchanted by and afraid of Benji’s constant, unfiltered stream of consciousness.

Meanwhile, Eisenberg’s David is also impaired by anxiety, but he’s taking the prescribed meds and mostly keeping the cork in the bottle. That changes during a dinner monologue during which David lets it all hang out while Benji is taking a bathroom break. That moment makes it clear that Eisenberg can not only act, but, damn, he can write with the best of them.

The kinetic interplay between Culkin and Eisenberg is some of the best you will see this year. Both actors deliver career-best work. Culkin will probably garner the most buzz and almost certainly get a supporting actor Oscar nomination, while one could expect a screenplay nom for Eisenberg. His directorial powers should not be under-estimated.

Culkin’s Benji is a once-in-a-lifetime role that plays perfectly into the performer’s wheelhouse. It’s funny; it’s scary; and it’s the sort of performance that will be viewed a hundred years from now as masterful and complete.