Producers: Dan Janvey, Derrick Tseng, Annie Baker and Andrew Goldman   Director: Annie Baker   Screenplay: Annie Baker   Cast: Julianne Nicholson, Zoe Ziegler, Sophie Okonedo, Elias Koteas, Will Patton, Mary Shultz, Edie Moon Kearns, June Walker Grossman and Abby Harri    Distributor: A24

Grade: B-

If you want to pigeonhole playwright Annie Baker’s debut feature, “Janet Planet” would qualify as a coming-of-age tale about eleven-year-old Lacy (Zoe Ziegler, flawless in her dour naturalism), a lonely, bespectacled outsider.  But as the title suggests, the girl’s free-spirited hippie-esque mother Janet (Julianne Nicholson, quietly empathetic but dreamy and often abstracted) is equally central, and it’s the parent-child dynamic over the course of the summer of 1991 that’s at the core of the film.

Baker’s script is divided into three parts.  The first is titled after Walt (Will Patton, gruffly compelling), the man living with Janet at the moment.  Lacy is off at camp, but calls to insist that Janet come and bring her home—in fact she threatens melodramatically to kill herself otherwise.  When Janet and Walt come to get her, though, she changes her mind after finding that her roommate actually likes her.  Too late: she’s back in her room at their rustic Massachusetts house, lonelier than ever.  (The fact that the beloved music box she keeps on her shelf of treasures, including a “cast” of petite dolls in candy wrappings that serve as players in her little theatrical shows, plays an excerpt from Mozart’s Requiem suggests a lot about the girl’s emotional state.)  Though Lacy’s other activities include desultory piano lessons with elderly, persistent Davina (Mary Schultz), the source of those chocolate wrappers, and an outing with Walt’s young daughter Sequoia (Edie Moon Kearns) at a mall that goes surprisingly well, it’s the girl’s closeness with her mother that’s the anchor in her life.

And it’s endangered, as far as she’s concerned, by the presence of Walt, who finds the girl’s habit of sleeping with Janet peculiar.  And when he comes down with a migraine that turns him demanding and nasty—especially toward Lacy—he disappears quickly from the scene after Janet asks her daughter whether she should break up with him, and the girl simply says she thinks so.

The second act is named after Regina (Sophie Okonedo, assertive yet quizzical), an old friend of Janet’s who’s involved in a cultish local theatrical group with whose pompous director Avi (Elias Koteas, wonderfully supercilious) she’s involved.  Baker treats us, if that’s the right word, to a sequence from one of their pretentious outdoor performances, filled with music, elevated dialogue, and extravagant costumes and masks. When Regina breaks up with Avi, she moves in with Janet and Lacy, penniless but free with her opinions, which she shares in mature conversations with Lacy and well as her mother.  Her observations on motherhood begin to irritate Janet, and when Avi drops by, supposedly to check on his ex, Regina disappears and he moves in.

In the final act, Janet listens attentively to Avi’s ponderous explications of deep existential questions, and her owlish, inquisitive daughter takes it all in—not just his long-winded pronouncements, often couched in the form of supposedly Socratic question sessions, but Janet’s reactions.  In the process one can sense Lacy coming to doubt whether Janet, who increasingly admits her regrets and uncertainties, should be the absolute center around which her own identity rotates—her planet, as it were.

“Janet Planet” avoids the clichés that usually afflict such stories about young adolescents beginning to detach themselves from a parent’s orbit.  There’s tenderness in the depiction of both mother and daughter, but it’s tempered with a glinting asperity, and never lapses into sentimentality; and while the other characters aren’t treated as buffoons, their frailties are made evident, not merely in the performances but in dialogue that, while it can occasionally veer toward the theatrical, has the knife-edged precision one expects of an accomplished playwright.

The narrative qualities are mirrored in the film’s look which, in Teresa Mastropierro’s production design, Lizzie Donelan’s costumes and Maria von Hausswolf’s cinematography, is realistically plain; the choices that Baker, von Hausswolf and editor Lucian Johnson make keep the characters close, the framing of the compositions simple and the tempo leisurely (sometimes excessively so).

“Janet Planet” is a decidedly insular but cumulatively incisive portrait of a daughter growing up in the world of an unconventional mother herself still searching for answers, rescued from dreariness by sharp writing and penetrating performances down the line.