This one is for his grandparents.

Playwright Raul Garza spent his childhood visiting his grandparents in Roma, the small Texas border town whose history begins in the Spanish colonial period.

Though Garza's upbringing was suitably suburban in the greater Dallas-Fort Worth area, Roma's historical buildings and its deep traditions always intrigued.

Produced by Teatro Vivo, "Cura," which spins a version of the story of folk saint El Niño Fidencio, opens Thursday at Salvage Vanguard Theater.

It's the third play Garza — a founding member of the Latino Comedy Project — has had produced by the nonprofit theater company.

His first, "Fantasmaville," a satirical and imaginative look at gentrification, netted him the 2007 National Latino Playwriting Award.

His next, "Dos Pacitos," was a darkly comic and surreal adventure into a future Texas-Mexico border zone left to the anarchy of drug cartels.

But Garza has set aside the humor with "Cura." Situated in 1938 — "the last moment before this country became post-war and more complicated," Garza says — the play examines the complex spirituality and cultural meaning of El Niño Fidencio, a Mexican curandero or folk healer who was revered during his lifetime (he died in 1938).

Not recognized as a saint by the Catholic Church, El Niño Fidencio, whose healing gestures involved herbs and other folk remedies, still inspires fiercely spiritual "Fidencistas" who have established many shrines, including one in Roma.

"I was fascinated by the ambiguity of the curanderos' relationship with the Catholic Church," Garza says.

Curanderos exist in parallel with the officiousness of the Catholic Church, with people often paying equal tribute to folk saints and rituals (often pre-Columbian in origin) as they do to the codified Catholic ceremonies.

"It's a kind of nebulous spirituality, curanderos," Garza says. "And yet it's so old, it often seems new to people today."

Indeed, with its focus on herbal treatments, curandero traditions bear much in common with popular New Age ideas.

Garza's grandparents were El Niño Fidencio devotees, and in "Cura," Garza imagines a chain of events in which a woman's faith is tested in a moment of crisis.

Is the mysterious young man who has just appeared in town really El Niño Fidencio?

With its thoughtful overtones and melancholic mood, "Cura" is as much of a departure for Garza as it was for Teatro Vivo, which has built much of its reputation on snappy but warm-hearted comedies that draw from, and illuminate, the contemporary Latino experience.

(Garza is a longtime Teatro Vivo collaborator and currently serves on the organization's board.)

"There's no guffaws in this play," says Garza.

As he has with his other scripts, the playwright has pulled in his brother, musician David Garza, (formerly leader of the band DAH-VEED) to pen a score. To match the 1930s setting, the music bears echoes of period banda sounds.

Now that his grandparents have passed, Garza doesn't visit Roma anymore. "Cura" is his good-bye to the mystery-laced, history-laden town that's far off the beaten track.

"This is my farewell to Roma," he says.

jvanryzin@statesman.com; 445-3699