The decorous Rhode Island living room depicted in the first act of “Sheltered” is thousands of miles from the decorous Austrian hotel room portrayed in the play’s second act. But that distance is ultimately less striking than the emotional and tonal distance that Alix Sobler’s drama travels as it tells a story set in 1939.

Now on view at Theater J, “Sheltered” is an uneven work with a clunky way of pinpointing its themes. Still, with help from a couple of pivotal performances in director Adam Immerwahr’s production, the play takes us on a journey that is substantial and, in key moments, very moving.

Inspired by a true story, “Sheltered” tells of an American couple’s daring bid to rescue 40 Jewish children from post-Anschluss Austria by bringing them to the United States. To obtain the necessary visas, Providence residents Evelyn and Leonard Kirsch (Erin Weaver and David Schlumpf) first must find stateside homes for all the kids, a task the spouses are scrambling to accomplish when they invite their sort-of friends Roberta and Martin Bloom (Kimberly Gilbert and Alexander Strain) to dinner. The harrowing significance of the Kirschs’ mission becomes clearer during Act 2 in Vienna, as the couple struggles to decide which children to save — a process that culminates in a searing conversation with a mother (McLean Fletcher) who is wrestling with a terrible decision.

Sobler is an up-and-coming playwright whose plays include “The Secret Annex,” about Anne Frank, and “Certain Woman of an Age,” a collaboration with former Canadian first lady Margaret Trudeau. In “Sheltered,” she boldly gives the two acts very different timbres, eschewing sleek-play conventions for the sake of greater impact and meaning. (Theater J is mounting the script’s second production, following the 2018 world premiere at Atlanta’s Alliance Theatre.) The Providence dinner party features tense moments that illuminate both the Bloom marriage and Evelyn and Roberta’s relationship, but the scene also comically conjures personal foibles and social awkwardness. Early on seen rhapsodizing about Thornton Wilder’s then-contemporary play “Our Town,” Martin soon reveals a harder side, dismissing the threat to European Jews, making anti-immigrant comments and cruelly deriding his wife. But, drolly, he fails to notice Roberta’s ability to manipulate him — and he hogs the cheese puffs.

The Blooms’ now-dark, now-comic relationship has a payoff in Act 2, which is all suspense and anguished intensity. Crucial to the effectiveness of this sequence, and the production as a whole, is Fletcher’s portrait of the conflicted Austrian mother, Hani Mueller, whose terseness and physical stillness testify to her near despair. Even her seemly orange outfit, chosen with a careful eye despite the agonizing concerns she’s grappling with, underscores a heroic effort to keep it together in the face of catastrophe. (Kelsey Hunt designed the period costumes; Paige Hathaway did the scenic design.)

Rivaling Fletcher’s acting turn is Weaver’s depiction of Evelyn, whose energy and vibrancy break down as she begins to grasp the full horror of the European situation and the choices she must make. In another notable performance — this one semi-comic — Gilbert displays the pain and willfulness Roberta has all but buried beneath stoicism.

There was a bit of stiffness to Act 1 on opening night, which underscored the script’s sometimes heavy-handed staking out of themes including assimilation, racism and xenophobia. It’s credible that these complex issues might surface during such a dinner party, but the “Sheltered” characters often trot out relevant remarks (Martin’s isolationist sentiments, for instance, or Roberta’s feelings about lack of diversity in the world of “Our Town”) in an unsatisfyingly tidy way. Along similar lines, in Act 2, the play features a metaphor that has the nuance of a sledgehammer.

Sobler has said she wrote “Sheltered” in response to our era’s Syrian refugee crisis, and the play’s concerns are all too resonant at a time of anti-immigrant sentiment, family separations and anti-Semitic hate crimes. One wishes “Sheltered” didn’t give off a sense of a playwright diligently marshaling important themes. Still, the writ-large issues don’t obscure the powerfully affecting image of Hani, faced with an impossible decision, almost too grief-stricken to speak.

Sheltered, by Alix Sobler. Directed by Adam Immerwahr; lighting design, Colin K. Bills; prop design, Timothy Jones; wig design, Greg Bazemore. 2 hours. Tickets: $25-$69. Through Feb. 2 at Edlavitch DC Jewish Community Center’s Aaron & Cecile Goldman Theater, 1529 16th Street, NW. 202-777-3210 or theaterj.org.