Fantastic film 'Good One' captures the disappointments of adulthood

There’s a moment in writer-director India Donaldson’s fantastic debut feature “Good One” that’s so perfectly judged it took my breath away. The emotional fulcrum of the film, it’s a casual, almost throwaway line of dialogue in which a vital trust is breached and our young heroine receives a rude introduction to the adult world. The line will have reverberations throughout the rest of the movie, and presumably the rest of these characters’ lives. But Donaldson doesn’t oversell it, eschewing the expected melodramatic music cues or overwrought reaction shots. She just lets the camera sit on star Lily Collias’ face, half-obscured in the campfire light as she silently absorbs what just happened.

Watching the scene from my couch during the online component of this past January’s Sundance Film Festival, I marveled at how easy it might be for audiences at home — especially critics who appear to spend half the runtimes of their festival screeners posting on social media — to miss the moment altogether. But when I went to see “Good One” again at this year’s Independent Film Festival Boston, the crowd at the Brattle Theatre was so locked-in and rapt that a woman sitting behind me actually gasped aloud “Oh no!” when it happened. See, there’s a common misconception that the big screen is for spectacle pictures, and intimate dramas like Donaldson’s film can be watched at home without missing much. But I’d argue that small pictures such as this one benefit even more from the focus and attention one can give when the only light in the room is coming from the story you’re watching.

“Good One” rewards such an investment. A movie modest in scope but not ambition or impact, the deceptively simple story sends Collias’ 17-year-old Sam on a weekend camping trip in the Catskills with her tetchy, controlling father Chris (James Le Gros) and his shambling wreck of a best friend Matt (Danny McCarthy). Matt’s son Dylan — a childhood playmate of Sam’s — was supposed to come along on the trip as well, but bailed after another blowout with his dad. Matt’s recent infidelity has torn the family apart, a situation Sam is entirely too familiar with, given her own father’s previous misdeeds. Now she’s stuck being a referee and chaperone to two middle-aged lost boys, occasionally calling her girlfriend (Sumaya Bouhbal) wondering how she wound up along for this ride.

There’s a version of this film that one can easily envision being terrible, and ever since Sundance I’ve struggled with synopsizing it to friends, wary of painting a picture in which the wise and all-knowing Gen Z lesbian claps back at a couple of old-school macho blowhards in the woods. “Good One” is a far knottier and more empathetic movie than that, and I feel like it’s telling that the 40-year-old Donaldson wrote the screenplay partially in response to becoming a parent herself.

It’s a film especially attuned to relationship dynamics, and we get to know these three people pretty quickly. The bearish, boisterous Matt has always been like a fun uncle to Sam, making inappropriate jokes to wind up her stuffy dad. But now with his marriage and career in tatters, there’s a heaviness behind his humor. McCarthy plays him as a guy realizing a few years too late his antics aren’t funny anymore. Matt shows up dreadfully unprepared for their arduous hike, carrying a backpack overloaded with junk food and wearing blue jeans.

It’s clear that he and Sam’s dad ran out of things in common sometime after college, but Chris still keeps Matt around to make himself feel better about how badly he’s screwed up his own life. Everyone has that messy friend with whom you feel put-together by comparison. (If you don’t, that means you’re probably the messy friend. I usually am.) It’s a fearlessly uningratiating performance from ‘90s indie film staple Le Gros, playing the kind of guy who sees every interaction as a kind of competition, even though nobody else is trying to win. Maybe the most emasculating scene in the movie finds him trying to one-up a bunch of well-traveled college kids who can’t possibly conceive of him as a rival.

Donaldson leaves the camera on Collias’ face for the majority of these interactions. This is the actress’s first major role but she’s already one of the movies’ great listeners. We’re watching her watch them, seeing a young girl figuring out her place in not just their dynamic, but the adult world as a whole, which for better or worse she’ll be dealing with the same kind of controlling, obnoxious men. Sam’s given a very funny — if a mite too writerly — monologue about how her dad ended up with a new baby in his 50s, but for the most part she’s a pensive, reactive presence. Captivatingly so.

Donaldson is the daughter of Australian filmmaker Roger Donaldson, a proficient journeyman known for brawny thrillers like “Smash Palace” and “No Way Out “ (as well as my most shameful guilty pleasure, “Cocktail,” which is the closest Tom Cruise ever came to making an Elvis movie). His testosterone-heavy pictures share little in common with “Good One,” but have clearly informed its milieu. The most obvious influence is Kelly Reichardt’s “Old Joy” with its depiction of a fraying male friendship running out of gas on a camping trip. The younger Donaldson has a similar eye for nature and an ear like Reichardt’s for the spaces between lines of dialogue. In interviews she’s spoken of a sense of permission she felt after seeing Claire Denis’ “35 Shots of Rum,” another film in which a daughter almost wordlessly learns to see her father figure as a person and starts down her own path.

“Good One” — which is currently neck and neck with Christy Hall’s “Daddio” for the year’s best debut with the worst title — is a sympathetic, sadly understanding movie about the inevitable disappointments of adulthood. “Can’t we just have a nice day?” Chris asks his daughter, flexing his well-practiced gift for denial and letting her down one more time. Over the course of the trip, Sam comes to learn that sitting at the grown-up’s table is no picnic. Especially with guys like her father and Matt.

”Good One” opens Friday, Aug 16 at the Coolidge Corner Theatre.