The trio of good-natured young adults who twiddle and flirt their way through “Hannah Takes the Stairs” will not be to everyone’s taste. They’re awkward, and lack movie-star looks. They enjoy sex, but could take it or leave it. Ecstasy, rage, any of the more strident emotions — not really their thing. As for drugs, well, one of them really appreciates the antidepressants he’s on.

It seems fair to call them some of the best-behaved youth ever to be featured in a non-Disney production. And for that reason, writer director Joe Swanberg and the core cast of this perceptive, no-budget independent film, which opens today at the IFC Center as part of the theater’s “new Talkies” series, deserve a good deal of credit: Their characters are actually pretty interesting.

It’s a good thing, too, because there’s not a whole lot to the story. Hannah (Greta Gerwig), Paul (Andrew Bujalski), and Mike (Mark duplass) live in Chicago, where they work for a political Web log. Paul is a writer and Mike is a graphic designer; what Hannah does, beyond inspiring crushes from both of them, is anyone’s guess.

But she and her refreshingly unexaggerated youthful dilemmas are the focus here, and both emerge gradually to form a compelling, if not earth-shattering, portrait of the modern liberal-arts major. (it goes without saying that hannah, an aspiring playwright with funky glasses and cropped blond hair, is not the technical-school type.) At no point in the film does she literally take the stairs anywhere, but she does seem to favor the slow route through the post-college phase — dating casually, retaining a skeptical view of the working world, and engaging frequently in light bouts of self-examination.

Ms. Gerwig captures Hannah’s self-awareness without allowing any hint of her own to creep into the portrayal. Watching her play a makeup-free temptress who’s equal parts playful and earnest gives one the impression that she is really just playing herself. The same goes for her two co-stars, and there’s definitely something to be said for that.

These days, the documentary’s ability to capture people as they really are seems to be at a low point. having a camera in one’s face used to scare subjects stiff; now, the paradigm of reality television commands people to act out. Feature films like Mr. Swanberg’s, which is just one chapter in the new generation of American do-it-yourself filmmaking known as “mumblecore,” may be the antidote. With its warts-and-all vérité style and pitch-perfect dialogue — the script is mercifully free of the hyper-articulate banter favored by so many indies — “Hannah Takes the Stairs” illuminates the ways and manners, and a bit of the yearning, of its chosen generation Y subset with an almost anthropological attention to detail.

It’s that attention — to the virtues of genuine interactions and relationships in an unadorned visual style that approximates real life — that defines the “mumblecore” movement and separates it from the more stylized renderings of youth that permeate independent filmmaking, not to mention mainstream fare. The people behind “Hannah Takes the Stairs” (virtually every cast member gets a writing credit) are telling a story collectively, with an approach they all have an investment in. Mr. Bujalski, the director of two films, wrote, directed, and starred in 2006’s “Mutual Appreciation,” and Mr. Duplass’s feature debut as a director, the forthcoming “Baghead,” will costar Ms. Gerwig.

As per the loose “mumblecore” method, Mr. Swanberg, who also shot and edited “Hannah Takes the Stairs,” rarely cues the viewer with close-ups. The characters are so non-confrontational — apologies and self-deprecating jokes are the norm — that most of the drama (and romance) is embedded in nuances, like glances and fidgeting and the way two people sit on a couch. That said, it’s not exactly Victorian theater. The film’s opening scene shows hannah and her boyfriend Matt (Kent Osborne) showering together with all the self-consciousness of two kids at play in a pool. in the living room, they giggle as they pick towel-lint off her breasts.

Hannah and her suitors rely on a form of pre-pubescent role-playing to defuse sexual tension and avoid the potential awkwardness of straightforward romantic overtures. Paul confesses to Hannah his feelings by means of a Slinky “telephone,” while she conveys her interest in Mike by drawing pictures and playing shaky trumpet duets with him.

For most of its 83 minutes, “Hannah Takes the Stairs” is content to merely hint at the angst underlying the characters’ naiveté. Thankfully, there is no loner-poet-with-attitude like the one Ethan Hawke famously modeled in the 1994 generation X drama “reality bites.” but if Mr. Bujalski’s enamored but career-oriented nerd is the most endearing character, it’s partly because he’s left out of the film’s lackluster finale. Hannah’s conclusion, that she is “chronically dissatisfied,” is rather obvious, to say the least, and the film ends without really explaining her incongruently pessimistic view of life. She claims that people are “naturally terrible to each other” and don’t listen enough. but she doesn’t seem to have done anything worse in her life than break a few hearts that will one day heal, and the crowd she spends most of her time with is even less harmful.

Luckily, the bulk of Mr. Swanberg’s film succeeds in proving that that doesn’t mean there’s no life in them.

Through August 28 (323 Sixth Ave. at West 3rd Street, 212-924-7771).