“People Are Wrong!”: a trenchant commentary on electoral politics, or the title of a new Off-Broadway show? Alas, the latter. Julia Greenberg and Robin Goldwasser have written a rock musical about a New York couple who have acquired a place in the Catskills and are trying to plan their wedding there. It’s not hard to see why the Vineyard wanted the show. The last time the company co-produced a new tuner, it won the Tony for Best Musical.

This show, a co-production with Target Margin, is no “Avenue Q.” In fact, when the new homeowners run afoul of a cult at the local Agway, and discover that its leader may be an extraterrestrial, it rings closer to “Little Shop of Horrors”: They’re sisters in snarky botany.

New York is tolerably liberal when it comes to adventurous new plays; you can’t set foot in the East Village without stepping on a puppet. In musical theater, the city is downright reactionary. Most new musicals fall into a sonic black hole, neither the traditional Broadway sound nor anything resembling what the world listens to today. With its clever premise and unusually catchy score, “People Are Wrong!” is welcome. Believe it or not, this remains true even though the show is burdened with the wrong set, wrong direction, bad acting, wrong choreography, and a botched plot.

Ms. Greenberg, Ms. Goldwasser, and various people associated with the show hail from the Loser’s Lounge, the hipster collective that stages tribute concerts for the Bee Gees, David Bowie, Prince, and more. The plastic eyewear and three-piece band send a whiff of Northsix through the middle of Off-Broadway. You’ll hear some close harmony, a good ballad or two, and plenty of driving, guitar-heavy pop. Almost alone among new musicals this year, these songs get my high compliment: I’d rip them onto iTunes if I could.

If you like They Might Be Giants, you may like this show. And if you really like They Might Be Giants, you’ll really really like this show. Co-founder John Flansburgh himself turns up as Russ, the homeowner. Now I have many fond memories of TMBG, and not just from school dances. The hard truth remains that Mr. Flansburgh does not seem like much of an actor. Neither does much of the cast. If you consult the program, you learn why: They’re not actors.

The same goes for Ms. Greenberg and Ms. Goldwasser. For all their skill as songwriters, you find that they’re first-time playwrights. The script’s puzzling lack of structure, clarity, pace, and balance gets a lot less puzzling. What becomes doubly puzzling is why these eager tunesmiths were not subjected to a really tyrannical dramaturg.

Director David Herskovits hasn’t reined in the chaos. He buttresses a shapeless script with a shapeless set. G.W. Mercier’s scenery consists of a rear wall on which characters hang various totemic images from the story, and a floor swathed in acres and acres of verdant Astroturf. Good actors can save bad scripts: Posture, voice, and rhythm will do wonders. But almost nobody here can hold the stage. Not David Driver, who plays the cult leader Xanthus, or Ms. Goldwasser, who plays the Agway manager, or the cultists themselves.

As the narrator, Chris Anderson (an experienced actor) fights his material to a draw. Only Erin Hill, who plays Terri the homeowner, gives a performance that’s also a characterization. No surprise to discover that she’s done multiple Broadway shows as well as plenty of pop work, which may be the ideal training for this style. If the whole company were so seasoned, the show may not have stumbled. Still, I rush to add: Better a stumble in the right direction than a steady march in the wrong one.

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A century ago, a Russian Jew named Haskell Harelik immigrated to the tiny, goyish hamlet of Hamilton, Texas. He sold bananas for a penny, and befriended a banker and his wife. Before long he had a thriving dry-goods business and a bustling family. In time, it yielded a grandson with a flair for biographical drama.

Mark Harelik told his grandfather’s story in his 1985 play “The Immigrant.” He tells it again in a new musical version of the play that opened at Dodger Stages last night. I haven’t seen Mr. Harelik’s play, but on the evidence presented here, I’m inclined to think it was pretty good. The script deals with guilt, gratitude, forgiveness, and the uneasy dance of Jews and Christians. It tells its captivating story with warmth that doesn’t sink to sentimentality, and an admirable complexity. It has, in fact, too much of these virtues for its own good.

No disrespect to composer Steven M. Alper and lyricist Sarah Knapp. This is not your standard musical glop, but rather challenging work in the post-Sondheim vein of, say, Ricky Ian Gordon. (Okay, a little disrespect for Ms. Knapp, who is too fond of stars in the dark, and the like.) But the show piles its qualities too thickly. It is a chamber musical that runs nearly two and a half hours. Even an emotionally involving show with a sense of humor, which is what this is, grows tiresome before then.

Under Randall Myler’s direction, the four-person cast could not be more different than the ragtag bunch in “People Are Wrong!” Walter Charles has the right dry sternness for the banker. Jacqueline Antaramian makes Haskell’s wife nicely freaked out upon encountering Texas’s yawning, gentile embrace. (Brian Webb’s scenery features a massive painted backdrop, with enough open sky to make agoraphobics nervous. The program notes this is based on an “original scenic design concept” by Ralph Funicello, whatever that means.)

As the banker’s wife, the kind, churchgoing Ima, Cass Morgan has grace and charm. She wears straw-colored hair, a Southern drawl, and a gold cross with equal permanence. She makes the most of the show’s ecumenical highlight. After Haskell is accosted by anti-Semites, she asks the Christian God to protect her Jewish friend from Christian thugs.

As Haskell himself, Adam Heller strikes a terrific balance of seriousness, deep feeling, and humor. He conveys Haskell’s determination (which is good) and his pride (not so much). It’s to his credit that even late in a show that should have ended half an hour earlier, he makes his last encounter with his friend and patron moving. With actors so gifted, a show need not run this long to say this much.