When Aimie (Jiseon Kim), the lead character in the new film “In Between Days,” asks her friend Tran (Taegu Andy Kang) if he wants her to “do it for you” the way she saw in the movies, it is hard to imagine what skill she has learned from the countless sex scenes she has probably seen. When she ends up giving him a homemade tattoo, it comes as a bit of a relief, if only temporarily so. But when her handiwork begins to bubble and fester with infection, the scene illustrates the strides and pitfalls that teenagers make in their unguided march toward adulthood.

“In Between Days,” director So Yong Kim’s first full-length feature, is an adept coming-of-age story of a young girl drifting on the brink of maturity. Having moved to Canada from Korea with her single mother (Bokja Kim), Aimie struggles with her English classes and takes refuge from the pains of her life in her solitary friendship with Tran.

The language barrier helps underscore Aimie’s outsider status. Detached from childhood and struggling with the expectations of adulthood, she tries to find her footing in the new country. But rather than assimilate, she delves into studies of Tran. She learns his movements, interests, and desires in the hope of receiving the male attention she craves so desperately.

As Aimie’s mother tries to move on and start a new relationship, Aimie holds imaginary conversations with the father who abandoned her and drops out of her English class to spend more time with Tran. But even as she tries to win him over, her actions often push him away.

Though she is successful in becoming his friend, Aimie’s feelings for Tran go much deeper, and her inability to express them becomes a minor tragedy in her life. Tran does have feelings for Aimie, but either can’t or won’t express them. It all falls apart when Tran passes Aimie over for a more Americanized Korean girl named Michelle (Gina Kim).

So Yong Kim grew up a Korean immigrant in the suburbs of Los Angeles, and her proximity to the project shines through the final product. She chose two non-actors for this study in adolescence, and their rapport is realistically unsteady.

Ms. Kim’s Aimie has an introverted beauty that occasionally shines brightly. Her ruddy skin and slightly off-kilter looks are endearing and provide a perfectly natural complexion to the role. Mr. Kang’s Tran is alternately aloof and endearing, and manages to demonstrate well how easy it is for young men to take advantage of a girl’s affection without realizing it.

The script was rewritten to fit Ms. Kim and Mr. Kang’s personalities, and they fit into character seamlessly, while the cinematography fittingly adds to the reticence of the film. Cinematographer Sarah Levy does some interesting work with reflection, watching the two leads looking at each other and stealing their image from reflective surfaces throughout.

“In Between Days” is a quiet and nuanced look into the unknown variables of adulthood that transfix and perplex teenagers as they fumble to find their footing. The added barrier of language and the reflective cinematography, often bouncing and distorting the images of its stars, lend an interesting depth to the adolescent tale.

As Aimie gives up choices that could positively affect her future to attach herself to Tran, it becomes all too apparent that he hasn’t similarly included her in his plans. Hers is a losing bet, but one that often seems so viable before one learns otherwise.

mkeane@nysun.com