The comedian's directorial debut is a real charmer, and it announces the arrival of a thrilling new talent in lead Elsie Fisher.

You’re going to fall in love with Elsie Fisher. As the breakout star and big, beating heart of Bo Burnham’s feature directorial debut, “Eighth Grade,” Fisher is tasked with carrying an entire film — an achingly real, firmly modern coming-of-age tale – with honesty and vulnerability to spare. The moment audiences meet Fisher’s character, soon-to-be middle school grad Kayla, she’s staring straight into her computer, delivering a motivational speech about “being yourself” that she will then upload on to her YouTube channel.

But Kayla isn’t some social media star, and her video ends with a halting plea for more likes and more shares. For a kid like Kayla, an outcast who is mostly ignored by her peers, the internet provides just another place for her voice to go unheard.

She ends her video, like all the others, with a single word: “Gucci.” It’s a cool-kid thing, hip slang that her youngsters are using these days, and in Kayla’s voice, it sounds terribly wrong. It’s also terribly funny. Burnham, best known for his stand-up comedy, music, and, oh yes, his own YouTube career, has certainly made a funny film, but he’s angled for the kind of laughter spawned by recognition, and there is so much to recognize in Kayla.

It’s remarkable that Burnham — yes, a man — has delivered a film like “Eighth Grade,” which is so deeply rooted in the feminine adolescent experience that it often feels as if he must have cracked open a whole mess of girls’ diaries to pen it. Burnham was initially moved to write about how social media impacts our lives, before abandoning the idea for something a little lighter, and perhaps even more true.

Kayla has just one week in eighth grade, and it’s evident that this shy, sensitive, creative kid hasn’t caught too many breaks in middle school. It’s not that she’s actively bullied, it’s that she’s just not noticed, thanks to a combination of her quiet personality and the deep self-absorption of the rest of her peers. Kayla’s happiest times are spent in the endless scroll of Instagram and Twitter and whatever else it is that teens are into these days, and she loses herself in the curated lives that everyone else seems to be living just a screen away.

But Kayla is curating her own lives — and lies — just like anyone, thanks to her arrestingly open YouTube page, which is dedicated to happy videos that see Kayla doling out advice on topics she knows nothing about.

In short, Kayla is lonely. She knows it, we know it, even her doting dad (a wholly lovely Josh Hamilton) knows it. But Kayla, for all her fake self-help mumbo-jumbo, is also smart enough to recognize the key to moving past all that: basically, just totally faking it. Trundled off to a cool-kid party — a pool party, true hell for an awkward eighth grader— Kayla vacillates between a full-bodied anxiety attack and pushing herself to sing karaoke in front of her slack-jawed peers (behavior that hits on yet another universal truth: Teens are impulsive and dumb and self-sabotaging and strangely free).

At every turn, Fisher is honest and open, relatable to the point that you feel as if you’re actually watching her own life play out (Fisher actually spent her own post-eighth grade summer filming the project). “Eighth Grade” isn’t a documentary, but it hews as close to the modern coming-of-age experience as currently seems possible.

Kayla’s newfound bluster is initially met with some major rewards, including a cool new high school friend (Emily Robinson) who takes Kayla under her wing and offers a glimpse of what the next chapter in her life could be like. However, her fortunes change with all the sensibility of, well, anything that happens in adolescence. While Burnham’s film is disarmingly good-hearted, he does allow some darkness to creep in, especially when it comes to her interactions with boys, though even the most uneasy of situations ultimately allow Kayla to more fully embrace her true desires.

Early in the film, Kayla and her fellow students celebrate their final week of eighth grade with a queasy gift: Time capsules they each assembled during their first week of sixth grade. Kayla’s capsule is bold, a shoebox adorned with the words “To the Coolest Girl in the World.” Her predictions for herself – all that coolness! – have not come true, and her disappointment in what the last three years have held is palpable and heartbreaking. If she’s not the coolest girl in the world, who is she? She’s something better: the most lovable girl in the world.

Grade: A-

“Eighth Grade” premiered at the 2018 Sundance Film Festival. A24 will release it in 2018.

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