“Ghostlight” is an intimate, moving indie drama about the transformative power of art and the mental health benefits of the theatre.

An “actors’ picture” in the purest sense of the phrase, its players take us on an emotional journey that covers limited ground, but manages to be an enriching, deeply rewarding experience nevertheless.

Keith Kupferer stars as Dan, a gruff highway construction worker sleep-walking through his days jack-hammering streets and sidewalks in his corner of Illinois.

Dan, we quickly learn, is getting it from all sides. He’s got an out-of-control teen (Katherine Mallen Kupferer) at home, a passive, sometimes-impulsive wife (Tara Mallen). And every pedestrian wanting a little peace and quiet and every rude, rushed driver feels the need to yell at the 50something laborer in the orange vest.

Something’s going on, driving all that domestic dysfunction. Daughter Daisy might get kicked out of school. There are “depositions” to prep with a lawyer, and counselors to drag Daisy to.

It’s enough to make Dan snap. But just as he does, this pushy little woman (Dolly De Leon) who has been complaining about the noise drags him into a storefront.

“I need your help with something.”

That “something” is a theater company she’s in. They need warm bodies, and Dan? He has the look of a Capulet. Wait, what is this?

“Your salvation,” Rita assures him. She looked Dan up and down, saw him mel tdown, and figured “you might like being somebody else, for a while.”

“Ghostlight” scampers past that unlikely turn of events and hurls this Blue Collar Joe into breathing exercises, limbering-up techniques and the “Provocative Questions” game, something actors play to measure, improve and acknowledge “emotional intelligence,” put themselves in another’s shoes and be “available” “in the moment.”

Dan, bottled-up and burdened by a sea of troubles, starts to connect to himself, his family and their problems by rehearsing “Romeo and Juliet.”

“Isn’t the language gorgeous,” a castmate enthuses? “I just wish I knew what it meant,” Dan admits.

Actress-turned-writer/director Kelly O’Sullivan and co-director Alex Thompson (“Saint Frances”) manage to make a generally unsurprising melodrama into a life-affirming delight.

So much of this is “on the nose” and predictably-sweet that “Ghostlight” flirts with becoming maudlin.

The novelty of casting a real-life couple, veteran stage actors, and their daughter, in the lead roles is cute enough to almost overwhelm the slight story and its “We all saw THAT coming” twists.

It turns out that the fiery Daisy knows Shakespeare, has the play memorized and was — until recently — a regular thespian in her high school. She too might be “transformed” by this amateur production.

But the players make the sale, and make this picture sing. The performances are mostly-understated, with barely glimpsed simmering fury in scenes where it isn’t evident. The youngest Kupferer takes things believably over-the-top as a mouthy, volatile teen in crisis.

The play within the picture is also “on the nose,” as far as subject matter. But as anybody who appreciates the Great Works of the Theatre knows, even the most shambolic “Romeo and Juliet” can come off, if the performances allow it.

De Leon’s Rita is every pie-eyed dreamer who fell in love with the stage, never came close to making it and yet never can let it go.

There are plenty of theatre nerd chuckles in the stumbling rehearsals, the unconventional casting and the “drama” behind the drama — demands for “an intimacy coordinator” on set — small-timers with big egos, older actors finding the soul of teen love and impulsiveness, or the perfect song to contemporize a 430 year-old play.

The miracle of “Ghostlight” is that cast and crew here take the punch-lines associated with actors and acting, the dreamy delusions its often overly-sensitive practitioners are famous for, and turn them into the greatest gifts acting gives to actors.

Emotional availability and “healing” might be just down the street with a bunch of cockeyed dreamers who just want to “put on a show,” with or without an intimacy coordinator.

Rating: R, fisticuffs, profanity, adult subject matter

Cast: Keith Kupferer, Katherine Mallen Kupferer, Dolly De Leon and Tara Mallen.

Credits: Directed by Kelly O’Sullivan and Alex Thompson, scripted by Kelly O’Sullivan. An IFC release.

Running time: 1:54