When streaming was still new, I had a notion that it might be the perfect place for movies and filmmakers who’d rarely fill-four-corners of a theater with their work, the creators of romances, dramas and thrillers on a smaller scale.

Who’d have figured that sci-fi, comic-book content and streaming “blockbusters” would take up as much bandwidth as they have?

“Flora and Son” is the latest from the musically-romantic Dubliner John Carney, who gave us the Oscar winning “Once,” then “Begin Again” and “Sing Street.” It’s an adorable small-scale romance with music, a film that’s perfect for a short theatrical run and a good reason to sign up for Apple TV+, where it will stream afterward.

It’s a tale set in Dublin and LA’s Topanga Canyon, a digital-age tale of connection through Facetime and music and a single-mom growing up at about the same time as her 14 year-old son. It’s adorable.

Eve Hewson of “Tesla,” “Bridge of Spies” and the “Papillon” remake has the title role, a too-sexy-for-her-own-good 30 year-old still hitting the clubs, drinking too much and bringing guys home. When they wake up/sober up and realize she has a 14 year-old son?

“You said you were ‘COOL’ with it” is all she can get out and the race to the door.

She and son Max (Orén Kinlan of “Sunlight”) fight like a doomed couple heading for divorce, cutting cursed insults that aren’t a sign of love, but deep dysfunction. Flora scrapes together enough money to house them and keep herself in smokes and wine through childcare and waitressing jobs.

The kid? He’s a burden, the abortion her friends couldn’t warn her into getting at 17. His acting-out includes a lot of petty theft and a “one more time” and you’re in juvenile detention lecture from the Garda (police youth liaison officer) who never calls Flora out for her partial blame in all this.

“Sometimes I’d like to come home and he just wasn’t there,” she tells her classmate (Marcella Plunkett) who got around to having a baby much later. That’s enough to make Aisling call her the same name her ex (Jack Reynor) uses.

“Psycho.”

She even forgets her own son’s birthday. Spying a guitar in a dumpster, she gets it repaired and gives it to him, but he’s not biting. Oh well. Maybe the ex-wife of a formerly-promising bass player can pick it up, “commit” to something for once in her life and learn to play well enough to write her own songs.

There are tons of tuturoials for aspiring musicians (and pretty much anything else) on Youtube these days. After rejecting the “posers” and not-very-good teachers, she latches onto Jeff. Sure, for $20 a week, she’ll give him a try.

Hewson brings an earthy, overripe vitality and Irish outspokenness to Flora. Joseph Gordon-Levitt becomes the living embodiment of the soulful, sensitive West Coast singer-songwriter.

He comes on all mellow, laid-back and catering to her needs, wondering “What do you hope to get out of this?” She’s evasive, maybe wanting to be taken seriously, possibly wanting to “win my ex back,” perhaps envisioning a better pool of men becoming available in a pursuit she’s always seen as “just sexy.” And she’s not having any LA airs from Jeff, thank you.

“Yer teachin’ guitar online, luv.”

And “you’re…Irish,” is the best he’s got for a comeback.

Carney’s great-gift as a filmmaker is bringing heart to musical moments of creation. Jeff sings a song he’s written as a country boot-shuffle, then again as an introspective ballad, and Flora, like the viewer, is taken aback and moved. To top that, he covers “I Get Along Without You Very Well,” which stuns Florda, who doesn’t recognize it as being an American Songbook standard by Hoagy Carmichael.

When he gives her homework, and it’s Joni Mitchell singing “Both Sides Now,” she is touched by the on-the-nose expression of her mental state, and the simple profundity a great tune like that or “I Get Along Without You” shares, that “three and a half minute pause in time” is how Jeff puts.

The “lessons” scenes have Flora envisioning this romance novel/Hallmark Channel romantic ideal at the same kitchen table with her, in the same park where she Zooms one lesson, or on the rooftop of her grim Dublin flat. They’re magical and give one a new appreciation for a filmmaker who is able to create that, seemingly at will.

“Flora and Son” is about music’s impact on Flora and her aspiring rapper son, their discovering their first real connection, about him facing the music of his choices and her facing the arrested development that her narcissism betrays. .

And it’s all set in post-card pretty or inner-city grey Dublin, from Griffith Park to Temple Bar. If that isn’t what movie streaming was invented for, I don’t know what was.

Rating: R for profanity, sexual references and brief drug use

Cast: Eve Hewson, Orén Kinlan, Jack Reynor, Marcella Plunkett and Joseph Gordon-Levitt.

Credits: Scripted and directed by John Carney. An Apple release, in theaters Sept. 22, then moving to Apple TV+.

Running time: 1:37