‘Kimberly Akimbo’ Review: What’s an Anagram for ‘Wonderful’?

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 on 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.