In the stirring yet unsatisfying documentary “Becoming Chaz,” which airs Tuesday night on OWN, a Los Angeles woman who has lived a life of relative despair (including the death of a lover, the stillbirth of a singing career and a struggle with painkiller addiction) can only truly heal herself by becoming himself. We follow Chaz Bono through a significant part of the process that took place in 2010, including hormone treatments and the surgical removal of his breasts.

As many know, Chaz Salvatore Bono was once Chastity Sun Bono, born in 1969 during the pop heyday of her parents, Sonny and Cher. (The Bonos were so saturated in show biz that they named Chastity for a disastrous movie project that same year, directed by Sonny and starring Cher.)

When Sonny and Cher’s variety show hit big on CBS in 1971, Chastity became a useful prop — the shy, towheaded cutie in baby-doll dresses and Mary Jane shoes who was brought out at the end of every show to blow goodnight kisses to America. Some of “Becoming Chaz’s” best moments feature clips from that time, with a heightened, melancholy regard for the scared girl who is frozen in stage lights and paparazzi flashes.

That essential anguish, now coursing with injected testosterone, remains. “Becoming Chaz” is one thing — and it’s occasionally fascinating to watch — but being Chaz gets old pretty fast.

As his longtime (and long-suffering) live-in girlfriend observes, Chaz’s change has also meant that she has become a lesbian with an overweight, temperamental, 42-year-old boyfriend who sits on the couch and plays video games all day. He’s become “a real [male appendage],” she says. Which, to Chaz, sounds like high praise indeed.

After its debut at Sundance earlier this year, “Becoming Chaz,” directed by Fenton Bailey and Randy Barbato, was immediately purchased by Oprah Winfrey’s new network as an example of just the sort of programming values Oprah wishes to exalt.

Indeed, the film encourages inquiry and open-mindedness; it tenderly attempts to explore a deep discomfort in both its subject and its potential viewers; and it is at times as difficult to look away from as it is to watch. If anything has characterized OWN since its debut in January, it would be this fascination with human difference, emotional fragility and social marginilization. All that, plus sutures, needles and drainage tubes.

But most of all, “Becoming Chaz” is about living just within the reach of celebrity’s hot glare, which is another of OWN’s fixations, demonstrated in the network’s reality series about the Judds, Shania Twain and, soon, Sarah Ferguson. No matter what Chaz becomes (or hopes to become), the lingering effects of his parents’ fame colors all of it.

A lot has happened since the ’70s, of course. Cher embarked on a never-ending journey of reinvention and self-preservation; Sonny became a politician and died in a 1998 ski accident while serving in Congress. Though focused on the life of a transgendered person in progress, “Becoming Chaz” can’t help but discover themes of abandonment and loss.

The film is also an inadvertent study in message and media management — starting with the fact that Chaz is credited as one of the film’s producers, thus exercising some control in what we see. Aside from the prying eyes of TMZ and “Entertainment Tonight,” much of Chaz’s PR maneuverings concern his mother’s public reaction to his gender change.

Cher looms distantly and mostly unseen, providing still more fertile OWN fodder — when mother-daughter issues become mother-son issues. When she at last makes herself available for a single, awkward interview, we are treated to the galling spectacle of a 66-year-old woman with that much cosmetic surgery describing her bewilderment at her son’s fixation on image, body and identity. Cher, long regarded as the ultimate GLBT pride parade marshal, now grasps for pronouns (he? she? her? him?) while talking about Chaz on “Late Show With David Letterman.”

It’s interesting to see her struggle with all this as a diva first and a mother second. Chaz, watching a tape of Cher’s interview, is both forgiving and cutting when he blames his mother’s response on her advanced age.

A few other questions go unanswered: Living in relative comfort with his girlfriend and a menagerie of dogs and hairless cats, does Chaz subsist on his share of Sonny’s estate? Does Cher help out financially? (Not with the surgical costs, it appears, as we learn that Chaz has borrowed money from his AA sponsor for the breast-removal procedure. Once again, a documentary about transgender surgery has failed to provide specifics about costs and financing.)

For all its honesty, “Becoming Chaz” averts difficult details and is saddled with an agenda: Chaz’s only career opportunity, it seems, is as a spokesman for transgender rights. What other future can await him, besides the discovery that he’s acquired a hairy back?

Becoming Chaz

(90 minutes) airs Tuesday at 9 p.m. on OWN. An audience discussion of the film, hosted by Rosie O’Donnell, follows at 10:30 p.m.