In musicals, the Marriage of elements is everything. A story that’s too thin will dissolve when mixed with the songs. A story that’s too heavy won’t let the songs lift off. To get the right fizzy blend, the balance must be perfect.

That is not yet the case with Mira Nair’s “Monsoon Wedding,” which opened Monday in an always busy, sometimes touching, but strangely mild production at St. Ann’s Warehouse in Brooklyn. Its shambolic plot lines (drawn from Nair’s 2001 film of the same name) and Indian-pop-meets-marching-band songs, though full of interest individually, fail to build on themselves or one another, leaving the intertwined tale of love and obligation to unravel as fast as it spins.

Not that the movie was a landmark of pith. The arranged marriage of the rich “South Delhi girl” Aditi Verma (played here by Salena Qureshi) and the U.S.-raised Hemant Rai (Deven Kolluri) was but one strand of a multifamily, multigenerational tale arranged in a riotous collage of small, colorful scenes. It didn’t matter how many went nowhere; the editing was all.

The musical tries to maintain that quick-cut effect while also squeezing the material into a traditional musical theater format. Nair told The New York Times she’d been inspired by the example of “Fiddler on the Roof,” a classic that, like “Monsoon Wedding,” encompasses one family’s marital chaos as part of a community’s encounter with tradition and change.

But “Fiddler” was adapted from a collection of short stories about a strong central character, not from a movie about many. The difference shows. The musical’s book, by Arpita Mukherjee and Sabrina Dhawan, is all over the place, and as staged by Nair on an abstract courtyard set by Jason Ardizzone-West, you rarely know where that is. The production seems to think in camera terms, as if a lens were still directing the audience’s attention when in fact nothing is.

I’m not sure anything could. Along with the frenzy of assembling the enormous celebration, the musical, like the film, encompasses a secondary comic romance between Dubey, the wedding planner, and Alice, the Vermas’s put-upon maid. The marriage of Aditi’s parents (Gagan Dev Riar and Palomi Ghosh) also gets a look, as do the romantic ideas of a tweenish cousin and a gayish brother, would-be in-laws, other relatives, local workers and (it sometimes seems) all of Delhi.

Nair does create musical-like texture by pulling some of these stories forward while pushing others back. The problem that threatens Aditi’s marriage — she is not yet over her affair with a married man — is recessed so far it essentially disappears upstage, depriving the crisis of serious tension. In its place we get the milder problem of deracination, since she will have to move to Hemant’s home in the States: Can she learn to love New Jersey?

The problem that threatens the marriage of Dubey (Namit Das) and Alice (Anisha Nagarajan) has on the other hand been upgraded from almost indecipherable in the movie to very serious indeed: In a country born in bitter partition, ethnic or religious divides of any sort — he’s Hindu and she’s Christian — can be harrowing. The resolution is facile (“the heart never tells a lie”) but at least it’s in a song.

That song, sung by Dubey’s mother (Sargam Ipshita Bali) to her overwrought son, is lovely, one of the few with a clear personality among 22 in a score that too often feels like a collection of snippets. In one, the gorgeous “Madhaniyan,” Aditi’s father bids her farewell on the eve of the marriage, pulling the same strings as “Far From the Home I Love” in “Fiddler.” (Well, not quite the same strings; the excellent eight-person band is highlighted by a sitar.)

But gorgeous or not, the score (music by Vishal Bhardwaj, lyrics by Masi Asare and Susan Birkenhead) is, like the script, all over the place. When the style, whether American or Indian, occasionally matches the characters and situation, the alignment makes the moment pop. An absurd production number called “Chuk Chuk” (for the sound a train makes as Dubey chases one to win Alice) sounds straight out of Bollywood, and with its cinematic projections (by David Bengali) and frenetic choreography (by Shampa Gopikrishna) it fits the dramatic moment in a way that excuses its utter lack of logic. A white horse is involved.

Otherwise, the musicalization feels both too assertive and too inconclusive, like a parade passing by. (There are rarely buttons on the songs to tell you they’re done, leaving the audience wondering whether to applaud.) Only in one song is there a concerted approach to the dramatic experience. The song involves Aditi’s orphaned cousin Ria, raised with her as a sister. Serious and studious, Ria (Sharvari Deshpande) plans to attend New York University, mostly as a way of escaping the marital expectations that Aditi, a pampered princess — “even your panties are ironed” — is all too willing to meet.

That Ria is also escaping a social atmosphere that tolerates the sexual abuse of girls is a theme that Nair emphasizes much more strongly here than in the film. But powerful as this is, especially in Deshpande’s performance, it is also destabilizing. It’s hard to make the leap from her late-Act II outcry, “Be a Good Girl,” to the happy ending, complete with exquisite saris (by Arjun Bhasin), a celebratory remix and the requisite double wedding.

How Ria became the central figure here — hers is the only solo number in the show — is a bit of a mystery, as if “Fiddler” decided to put Chava, the disowned daughter, above the title. Longer scenes (some are just three lines) might have helped explain the change, or shift our expectations in a show called “Monsoon Wedding” to the character who specifically doesn’t want to get married.

Still, you have to be grateful that Ria has elicited from the authors their most powerful writing. In “Leaving Means Returning,” sung to her by her stepfather, a lyric encapsulates in a beautiful phrase the tempting if ambivalent embrace of family: “We are your comfort and your courtyard.” Just so, genre is a place of safety but also a kind of prison. “Monsoon Wedding” does not quite escape either.

Monsoon Wedding
Through June 25 at St. Ann’s Warehouse, Brooklyn; stannswarehouse.org. Running time: 2 hours 30 minutes.