The characters in Irish director John Carney’s films are fundamentally good people down on their luck, stumbling here and there with the usual problems, which they try to overcome with a song in their heart.

“Flora and Son” is the latest from the director of “Once,”“Begin Again”and“Sing Street,”and it’s another winning sweet tale of self-discovery through music. Resistance to this emotional, melancholic gem is futile.

Flora (Eve Hewson of“Tesla”and the Apple TV+ series“Bad Sisters”) is a single mother of a troubled teen, Max (Orén Kinlan), who is right on the edge of being remanded to the Irish version of juvenile hall. Max’s father, Ian (Jack Reynor of“Midsommar,”“The Good Mother”and the Prime Video series“The Peripheral”) is still on the scene, but he’s more interested in his struggling Dublin club band than his responsibilities.

当植物发现吉他定于垃圾bin, she decides to learn to play as something to help her get through difficult times.

She surfs YouTube videos for lessons, and stumbles upon a guy in Los Angeles who gives virtual guitar lessons. He’s Jeff (Joseph Gordon-Levitt), a talented musician and songwriter who has a painful backstory of his own.

He’s an excellent teacher and a good listener. Soon their conversations run deep and personal.

“That song has 20 years of heartache and life,” Jeff says after strumming a tune.

“You sort of calm me down,” Flora responds.

Maybe they’re falling in love. But Flora comes to a more important realization: Music might be the key to reaching her son.

As always in Carney’s films, the music is emotional and lovely, with instruments played by its actors. The songs feel like they’re improvised on the spot, and Dublin is as inviting of a setting as usual.

Hewson, 32, finally has a film worthy of her talents after more than a decade on the scene. The daughter of U2 frontmanBono, she has an edgy tenderness. Flora is a charming but defensive woman trying to fight through her insecurities and feelings of failure — she had Max when she was 17, so it’s been that kind of life.

Carney broke through with the crowd-pleaser“Once”in 2007, which starredGlen Hansardand Markéta Irglová as struggling Dublin musicians. It was an out-of-nowhere hit that played for months in the Bay Area and was later适应了圣age. Its song “Falling Slowly” won an Oscar.

It says something about the state of cinema exhibition that “Flora and Son,” a film of similar vibes and quality, opens in two small Bay Area theaters as well as streaming on Apple TV+. On the one hand, it’s nice that potentially millions can see the film on their TV sets. But this is a film that would be a great theatrical experience that could build organically with good word of mouth, and it’s too bad it’s not getting that kind of a shot.

Reach G. Allen Johnson:ajohnson@sfchronicle.com