Hell is other people, and when those people are your high-school peers, it's doubly true. It's doubtful that Sartre had that caveat in mind, but that's the ethos of plucky senior-high outcast Nadine in writer/director Kelly Fremon Craig's earnest and charming debut feature The Edge of Seventeen. Nadine (a radiant Hailee Steinfeld) is in her junior year and forlornly adrift. Her only friend is Krista (Haley Lu Richardson), with whom she's shared a bond since elementary school. They've been each other's rock through the ordeal of their preteen years and early adolescence -- which also included the death of Nadine's loving father. As her family has struggled through the pain of that loss, Nadine's older brother Darian (Blake Jenner) has managed to become a model student and athlete, as well as the golden child in the eyes of their now-single mother Mona (Kyra Sedgwick). Nadine, meanwhile, has been stuck in neutral -- she's constantly sparring with her family and unable to flourish socially in the dog-eat-dog world of high school, a fact that causes her to retreat into her coexistence with Krista. Thus, a late-night rendezvous between Krista and Darian, which eventually sparks a more serious relationship, feels like the ultimate betrayal to Nadine. Now friendless and even more at odds with the rest of her household, she finds herself spouting off during lunchtime to her reserved and cynical teacher, Mr. Bruner (Woody Harrelson). Later, she finds hope while spending time with her affable yet awkward classmate Erwin (Hayden Szeto); he, of course, desperately pines for her, but is stuck in the friend zone as she gawks over a bad-boy senior. As these events and relationship crises reach a snarky and comical climax, Nadine stumbles along in search of her identity. The Edge of Seventeen features plenty of angst from Nadine, who unleashes that specific brand of on-the-nose teenage haranguing about her technology-obsessed peers. She's brash and darkly comedic, vacillating from suicidal threats to wishful sexual propositions, and nearly impossible not to root for (bringing to mind Ellen Page's turn in Juno). The magnetic Steinfeld has the breadth to play this flawed protagonist: Instead of giving us a feature-length pity party for a social outcast, she's able to balance Nadine's adolescent self-absorption with a self-deprecating sense of humor. It's the perfect role for burgeoning superstar Steinfeld, and if we're lucky, she'll be gracing the silver screen for decades to come. Just outside of the heroine's dynamic glow is relative newcomer Hayden Szeto. The "awkward, brainy teen" character type is typically a disaster waiting to happen, but Szeto absolutely nails the nervous, deadpan Erwin (think of a less punchable Michael Cera). Fremon Craig's script sags slightly when Mr. Bruner comes to the forefront: By trying so hard to avoid painting him as a stock character full of down-to-earth adult wisdom, he's actually left with very little to say. Perhaps that's all Nadine needs at the moment -- someone to lend a sympathetic ear -- especially given that the picture isn't fully invested in exploring her widowed mother's grief. Either way, it's pretty common for the adults in a teen film to feel underwritten, and at least Steinfeld and Harrelson's shared screen time produces some of the funniest and most heartfelt moments in the flick. Fremon Craig does no such disservice to the teenagers at the movie's core, making each of them feel complex and believable. By not belittling the melancholies of adolescence and staying away from the twee trappings that usually come with this genre, Kelly Fremon Craig's debut rings true with authenticity. And thanks to its knockout cast, who manage to balance dark wit with dramatic competence, The Edge of Seventeen rises to the top of recent coming-of-age films.