The French writer-director Céline Sciamma has, in a matter of just three films, established herself as among our most sensitive and sympathetic observers of the young. 2007's Water Lilies and 2011's Tomboy found their protagonists at critical, formative junctures, and subtly nudged them towards some greater understanding of how the grown-up world works; her latest, Girlhood, expands this filmmaker's field of study in much the same way the inbound Eden does the canvas of Mia Hansen-Løve. We get some indication of Sciamma's increased confidence in her imagemaking from the opening scrimmage: schoolgirls in shoulderpads playing gridiron to the accompaniment of a blaring pop soundtrack. Given the generally quietist methods of Sciamma's previous work, this could be an American teen movie we're watching. (It's probably not coincidental that the film's distributors have selected an English-language title that rhymes with Richard Linklater's acclaimed history of growing up.)
If narratively Sciamma's film offers something relatively familiar, the story of a "good" girl who falls in with the wrong crowd, it's elevated by its heightened sense of time and place, its sure feel for those moments its teenage heroine - Marieme (Karidja Touré), the daughter of African immigrants living in the Parisian banlieue - must pass through to get to where she's going. We immediately understand Marieme's need to impose herself upon her surroundings and prove herself - against all socio-economic evidence to the contrary - no pushover: hence the football (a symbolic snapshot, never returned to), hence her decision to start carrying a knife, and to follow a gang of her contemporaries into pitched battle with local rivals. A generous, forgiving director, Sciamma sees the attraction in the pose. During a hotel-room singalong to Rihanna's "Diamonds", she punches up the blues in the frame - already something of a radical choice for a film about girls - and briefly turns Girlhood into a promo video with the slyest of editorial footnotes: in shining bright like a diamond, as the lyrics have it, these girls confer upon themselves a self-worth they aren't finding anywhere else.
What's especially sharp about Sciamma's gaze here is that she also spots the scared and vulnerable young things sheltering behind these poses. The daughter of a hotel cleaner (and expected to follow her mother into such work), Marieme sings about diamonds because she's unlikely to afford them herself; while her gangmates doll themselves up in pilfered evening gowns with the security tags still attached, she inherits a necklace rechristening her "Vic". It's supposedly short for "victory"; we're also inclined to believe it might be "victim". For even when this gang chooses to stand their ground and fight back, they risk humiliation: after being smacked down and forcibly stripped in one vicious playground brawl - her defeat inevitably recorded and uploaded to YouTube - gang frontwoman Lady (Assa Sylla) lapses into mute, wigless depression.
In its final third - charting Marieme's graduation from mean-girling to the (masculine) thug life - Sciamma's light touch begins to waver: events start to get just a mite conventional and melodramatic, overlapping with the themes and activity of any number of British crime dramas. Yet even this rough-and-tumble serves as a useful critique of Boyhood's hair-ruffling placidity: real shit happens to Marieme, beyond time passing. (Mason, by comparison, has it way too easy.) Putting in close, intimate work with her young, inexperienced performers - particularly with Touré, shown trying on personas like dresses in a makeover montage - Sciamma keeps generating fresh, unself-conscious displays and definitions of girlhood: singing into remote controls, posing for selfies, gossiping over rounds of crazy golf.
Though Water Lilies and Tomboy were much admired, they felt tentative in their narratives and methodology, visibly the work of a gifted young writer-director still finding her feet. Girlhood again unfolds as a series of decisive moments, small yet significant steps forward, yet it's far more forceful and persuasive in how it presents its findings, and a good deal less clinical than this technique suggests: as that opening scrumdown establishes, it's both alert to and alive with the tumult of teenage life, resisting the temptation of holding its protagonist up as a role model or at arm's length as a mere subject - perhaps, in part, because this director has been here, or hereabouts, herself. You can well imagine packs of actual teenage girls hunting the film down in the artiplexes of the West, and for once emerging without feeling remotely condescended towards. In Sciamma, this demographic may just have found their closest ally since John Hughes or Amy Heckerling.
Girlhood opens in selected cinemas from Friday.