Just one piece of the first Broadway revival of David Auburn’s most famous play answers the question “What exactly is ‘Proof’ + 26 years?”

That’s Ayo Edebiri, the ubiquitous actress from FX’s “The Bear” who plays grief-stricken Catherine, the role made famous more than a quarter century ago by a young Mary-Louise Parker. 

The setting of the tight-as-a-drum drama, which opened Thursday night at the Booth Theatre, hasn’t been moved from the early aughts. But Edebiri’s cringing, self-deprecating embodiment of a woman at her wit’s end couldn’t be more rooted in 2026 — much in the same way Parker’s lauded turn was a mascot for the new millennium. 

The original actress’ performance as a Chicago student whose renowned mathematician father has just died is remembered for its directness, assured control of her character’s sexuality and untethered energy. 

Edebiri’s scaled-back version, with nary a hint of any of that, has Gen Z written all over it. Catherine recedes when confronted. She runs toward geekiness — not away from it. She hides from others using a sense of humor that’s mainly for her own amusement, not for anybody else’s. Painful emotions make her physically tremble while she fights to keep them down.   

Admirably, hers is a very different portrayal of Catherine than any I’ve seen before. At times, it’s a very moving one. And, while Edebiri’s interpretation won’t please everybody or even gel with all the beats of the play — particularly older sister Claire and new friend Hal’s sexist insistence that Catherine couldn’t possibly be a math wiz — the actress’ sheer modernity helps prevent “Proof” from feeling too retro.

Phew. Because director Thomas Kail certainly isn’t helping her on that front. 

On a bright University of Chicago backyard set by Teresa L. Williams that could be used on dark nights for “Home Improvement Live!,” the man who staged “Hamilton” sheepishly delivers an uninspired checklist of basic entrances and exits while batting away the many artistic possibilities Auburn’s script provides.

After all, this is a show that begins with a fantasized conversation between a fraying daughter and her dead dad, Robert, dispassionately played by Don Cheadle, and poignant memory scenes from past years fade in dreamlike. Her father also suffered from dementia, and in flashbacks we witness his bad days and lucid days. The mind’s power, or lack thereof, drives the story just as much as the familiar family fights that cement it as a traditional American play do. 

You see, “Proof” is packed with the potential for illuminating expressionism or thrilling deconstruction. There are ample opportunities to revive it. 

Nah, said Kail. Have a fake lawn.

Stomping on plastic grass with Edebiri is Claire, Catherine’s high-strung, put-together sister who lives in New York and contributed cash to dad’s care but kept her physical distance away from Hyde Park. Shocker — that causes some friction. 

Kara Young, a brilliant performer who’s taken just five years to become a big reason Broadway audiences buy tickets, stands out as she always does. Her funny Claire, recognizable to anybody with a critical sister, makes so many statements with her hands it’s like she took a communications course at Cobra Kai. 

As entertaining as Young is, though, her Claire is questionably sized bigger than Catherine, dad and Hal (a sweet Jin Ha), the hunky-dorky math student that Catherine is smitten with, putting the ensemble off balance. 

And she’s not the only one out of sync. Cheadle’s general nonchalance robs his role of would-be shattering moments of impact. Whether Robert is at his lowest, scribbling gibberish in a notebook in the frigid Chicago cold, or back to his old self taking Catherine to dinner for her birthday, he’s the same even-keeled guy. A powerful thread is thus snapped.

Yes, the show about mathematicians has its problems — Kail’s shrugging direction, such as it is, being the biggest. And yet Auburn’s ironclad script alone remains exceedingly enjoyable, especially for lucky newbies who don’t know the bombshell that’s coming. Add to that Edebiri, who, while not giving the career-defining performance Parker did, is nonetheless worth seeing. 

Unlike with a proof, a few out-of-place elements don’t always send an entire production into the trash bin.