Cretton's adaptation of Jeanette Walls' memoir isn't groundbreaking, but Larson's soulful performance elevates an otherwise straightforward drama.

Destin Daniel Cretton’s 2013 breakout drama “Short Term 12” delivered a heartwarming story with bite. His portrait of a home for troubled teenagers owed much to Brie Larson, who played its passionate supervisor with a mixture of empathy and rage against the flaws of a system designed to improve young people’s lives. It delivered a sentimental message without trumping its characters’ palpable rage and cynicism, and established Cretton as a director capable of generating emotion without pandering.

Cretton still makes that effort with his long-awaited followup, “The Glass Castle,” but with less success. While he has a fascinating story and another stirring Larson performance, the results are minor and decidedly more middlebrow.

Adapted from Jeanette Walls’ memoir, Larson plays the author as she grows up in a wildly dysfunctional household headed by her alcoholic father Rex (Woody Harrelson), who forces the family to live a nomadic, hand-to-mouth existence in a series of dilapidated West Virginia homes in lieu of finding a job. He’s joined by his idiosyncratic artist wife Rose Mary (Naomi Watts), who shifts between encouraging her husband’s grimy off-the-grid plan and contemplating taking their four baffled children elsewhere. As the oldest of the brood, Jeanette (played in extensive flashbacks by impressive newcomer Ella Anderson) takes charge of the situation, coaching her drunken father through long, brutal nights and ultimately confronting him about the need to improve their situation.

Jeanette leaves her family for college, and later builds a stable career as a gossip columnist in 1989 New York. There, she finds the parents she abandoned long ago. They’re squatting in an abandoned Lower East Side home, where Rex still rambles on about the ills of modern society and proclaims his grand ambitions to develop solar energy.

For a while, the movie generates a fascinating juxtaposition between Jeanette’s childhood efforts to improve her family’s circumstances and the tragic results, a mystery unfolding piecemeal. However, the movie becomes ever more familiar as it moves along, giving way to a tale of father-daughter estrangement.

While it’s been in development for years, “The Glass Castle” has the unfortunate distinction of coming out one year after Matt Ross’ “Captain Fantastic,” which also focused on an anarchic household raised beyond the clutches of civilization. (Charlie Shotwell, who portrayed one of the kids in that film, also appears here as young Jeannette’s brother.) But while that movie took on the form of a seriocomic road trip, “The Glass Castle” is more conventional and places more emphasis on the ramifications of Jeanette’s troubled childhood on her adult life.

Larson — who eventually plays Jeanette’s teen self in addition to a woman in her twenties — brings a soulful depth to the character’s inner turmoil over whether to reconcile with her relatives. However, a developing subplot involving her relationship with a bland financial advisor David (Max Greenfield) holds far less interest, and that becomes a central narrative once Jeanette struggleswith telling her anti-capitalist father that she plans to marry the guy. A vivid, unnerving story about dangerous parenting veers into a soap-opera subplot.

All of this maintains a polished cinematic quality, with credit going to “Short Term 12” cinematographer Brett Pawlak (“Hellion,” “The Meddler”). With equal attention to detail, he captures the griminess of the Walls’ decrepit homes and the brightly lit affluence to which the adult Jeanette retreats. Cretton resurrects a memorable closing effect from “Short Term 12” that finds characters dashing from one place to the next in slo-mo, and it’s a simple but effective means of showing how no matter how much effort Jeanette and her family places into dashing to a better place, they’re still tethered to the past.

If only it were a bit more believable. “The Glass Castle” may cull from real life, but Harrelson often turns the central threat to Jeanette’s stability into a blunt caricature, with bulging eyes and a crooked smile as his chief shorthand for a man intent on self-destruction. As the slightly more rational parent, Watts fares slightly better, but she still toggles between Harrelson’s loony extremes and understated asides to her children for reasons the movie never effectively explains.

Larson ameliorates most of these deficiencies. In the final act, she’s so in touch with the paradoxes of Jeanette’s adult conundrum that she singlehandedly elevates the movie above a rising tide of clichés. Larson’s nuanced performance expresses how she can resent her parents while being concerned for their well-being. “Your values are all confused” says Rex, in one of his more lucid moments.

As with “Short Term 12,” Cretton has found provocative material about people eager to make a change, but trapped by the limited resources at their disposal. However, that movie was a high-stakes journey into the lives of rebels and a world that conspired against them; “The Glass Castle” uses its unconventional backdrop only to set the stage for a more quotidian father-daughter showdown.

Still, even when the the music swells and people talk through their problems to reach unremarkable conclusions, there’s an undercurrent of emotional authenticity. To a large degree, that stems from Jeanette’s inability to completely abandon her wreck of a father. His cruel antics don’t alienate her so much as make her furious: She wants to make things better, and it tears her up that she can’t.

The movie arrives at a simple resolution that almost feels like a shrug, but there are hints of contradictions just beneath the surface. That’s not quite enough to elevate a story that sagged into predictability, but it’s further confirmation of Cretton’s rare gift for earnest storytelling that doesn’t preclude the darker aspects of life.

Grade: B-

“The Glass Castle” opens nationwide on August 11.

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