NEW YORK, NY.- The sweetest love scene on a New York stage right now involves neither Left Bank bohemians, Orpheus and Eurydice nor even that freak with the mask. Rather, it’s between a tuba-playing, elvish-speaking high school über-nerd and a girl who looks like his grandmother.

That’s because the girl, Kimberly Levaco, born with a genetic aging disorder akin to progeria, appears to be in her 60s even though she’s just turning 16. In the funny and moving new musical “Kimberly Akimbo,” which opened Wednesday in an Atlantic Theater Company production at the Linda Gross Theater, Victoria Clark brings her to life so believably and gorgeously that you find yourself rooting for a kiss you might otherwise find creepy.

That’s no surprise; Clark, 62, is one of our great singing actors, situating herself exactly where the two impossible arts intersect. In role after role — particularly as an anxious mother in “The Light in the Piazza,” for which she won a Tony Award in 2005 — she makes music not an afterthought to character but the thought itself.

What is surprising is that “Kimberly Akimbo,” based on the 2000 play of the same name by David Lindsay-Abaire, manages a similar feat. Unlike adaptations that do little more than nail vocal Sheetrock onto bare studs of borrowed story, and have approximately the same elegance, this one — with music by Jeanine Tesori and a book and lyrics by Lindsay-Abaire — remakes the original on new terms, with songs that beautifully tell us new things.

This is done without undue violence to the ingenious original premise, which makes comedy, as we all must, of tragedy. Kimberly is burdened not only by a disease for which the average life expectancy is 16 (“It’s just an average though,” she says brightly) but also by a family that has not handled it nearly as well as she has.

Her mother, Pattie (Alli Mauzey), is ludicrously hypochondriacal, as if atoning for the chromosomal accident that produced her quick-aging child. Her father, Buddy (Steven Boyer), is floridly irresponsible, reneging on promises and drinking himself into stupors. Her aunt Debra (Bonnie Milligan) is a cheerful, amoral tornado of bad ideas who squats in the Levaco basement to further a check-forging scheme. In a household filled with impulsive, appetitive childishness, Kimberly, who has to feed Pattie her morning cereal because both her arms are in casts, is the adult by default.

It’s that quality, more than her appearance, that makes Kimberly something of an outcast at school. The upside is that it draws her to the über-nerd, Seth, played in a terrific New York debut by 18-year-old Justin Cooley. Seth is plenty familiar with premature adulthood syndrome: His widowed father barely notices him, leaving him to figure out how to be a “good kid” (as one of his songs is titled) on his own. Recognizing that trait in each other, Seth and Kimberly bond over their parallel irregularities: his obsession with anagrams and her genetically scrambled codons.

Each of these subjects produces a wonderfully unexpected song that forwards the plot while deepening the characterizations. In the first, as Seth struggles to make an anagram of “Kimberly Levaco,” his strange stabs at solutions (“My blacker olive! My crablike love!”) form a kind of descant to her rapturous discovery of his “askew” point of view: “I like the way you look at life and think outside the box,” she sings. “A little odd. A little off. A bit unorthodox.”

And when students present science projects on ailments of their choosing in a hilarious ensemble number called “Our Disease,” Kimberly veers from the script she and Seth wrote about hers. Their classmates may have chosen scurvy and fasciolosis, but what they really suffer from is “a bad case of adolescence,” she sings. “Getting older is my affliction. / Getting older is your cure.”




Those classmates (charmingly played by Olivia Elease Hardy, Fernell Hogan II, Nina White and Michael Iskander) are the most obvious addition to the musical, having been invented to provide social context, a singing ensemble and broader humor. Less convincingly, Lindsay-Abaire ties them into the story as accomplices in Aunt Debra’s check-forging scheme; they hope to raise enough cash to buy spangly costumes for a show choir competition. Still, as this allows them to provide backup for Milligan’s barn-burning numbers, I won’t complain.

That Tesori can write any kind of music is old news. (For further proof, see “Caroline, or Change,” now on Broadway.) What’s apparent in “Kimberly Akimbo” is that she can also write inerrantly for any kind of show. It can’t have been easy to find the right moments and tone for songs in a double-sided story like this, where each joke is also a memento mori, and vice versa. (One number is called “The Inevitable Turn.”) Its sound world — including ukulele tunes, surprise double melodies and genial pastiche — most resembles that of stage musical “Shrek,” another collaboration with Lindsay-Abaire, but it takes its own inevitable turn, becoming richer and more yearning as the material demands.

As its star demands, too. I wish Clark had a bigger solo in the penultimate scene; we have by that time earned the right to a major statement from a performer capable of delivering it.

As long as we’re picking at excellence, I’ll add that “Kimberly Akimbo” isn’t yet all it might be. The New Jersey setting is clearly and wickedly characterized. but the era, supposedly 1999, is not; the father’s arc is not sharply inscribed; and the use of the high school students to fill out songs they don’t otherwise belong in feels unmotivated. Although acute in its emotional detail, Jessica Stone’s staging, on a vague set by David Zinn and with choreography by Danny Mefford, is physically underpowered. Scenes in an ice-skating rink might as well be set in an empty mall, for all the action they deliver.

But these are really minor complaints about a show that gets so many major things so right. “Kimberly Akimbo” is already the rare example of a good play that has become an even better musical. It warms up the zaniness of the original without overshooting and making it “normal.” Instead of cowering as if embarrassed by the dimension music can bring to drama, it embraces the ability of song, even in tragicomedy, to extend emotion into bigger realms.

And don’t let its pure enjoyability mislead you into thinking it’s not a tragicomedy. To see an old hand like Clark make sparks with a newcomer like Cooley is to feel how quickly the world spins forward. “No one gets a second time around,” they sing in the finale (although “Kimberly Akimbo” fortunately did). It may be an old-style “carpe diem” message — or a “mad recipe,” as Seth might have it — but in this case, leavened by exceptional craft, it makes a totally satisfying meal.

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‘Kimberly Akimbo’

Through Jan. 2 at the Linda Gross Theater, Manhattan; atlantictheater.org. Running time: 2 hours, 20 minutes.

This article originally appeared in The New York Times.