Until the feathers start flying and the satin starts flowing, there's not much in Mimi Le Duck - the muddy palette of an artistic inspiration musical that just opened at New World Stages - remotely resembling a human story. But once a million-dollar bundle of them are trundled onstage and unveiled in all their gaudy glory, they're electric enough to make any heart beat faster, even one at the center of an otherwise bloodless show.

That priceless treasure is none other than Eartha Kitt, who may be playing a disintegrating French chanteuse named Madame Vallet, but couldn't have her own act any more together. As she prowls about the stage, employing all the purring sensuality that's defined her 60-year career in show business - but which miraculously never gets old - her mere presence guarantees your rapt attention. And if she should happen to roll an R for a few seconds or - Lord almighty - flash her impossibly great legs... Forget it, you're gone.

But don't be fooled into thinking you're just watching Kitt. When an unfortunate accident sends her feathered headdress and voluminous wig tumbling to the floor, she shrinks in the spotlight like a frightened girl. The deflation is so immediate and so total that you cease seeing one of our greatest living theatre stars and instead see only Madame Vallet, a woman learning late in life that youth can't - and shouldn't - be held onto forever.

The sadness you feel at this spectacle - the greatest currently on any New York stage - is twofold: First and foremost, you might find yourself fleetingly wondering if Kitt (who's about to turn 80, but doesn't look or sound it) is considering what Madame Vallet now must; second, you know instinctively that nothing else in Mimi Le Duck can rise to this level.

For the transformation of Madame Vallet from perilously preserved flower to blooming maturity isn't supposed to be the dramatic centerpiece of the musical Diana Hansen-Young (book and lyrics) and Brian Feinstein (music) have written. The show's about emotional evolution, yes, but the real focus is Mimi herself - née Miriam Sanders (Annie Golden), a Mormon housewife from Ketchum, Idaho, who abandons her career painting canvases of ducks for sale on QVC in favor of life as a starving artist on the byways of Paris.

She's become disillusioned by 25 years of marriage to Peter (Marcus Neville), so when the ghost (yes) of Ernest Hemingway (Allen Fitzpatrick) beckons her Europeward, doesn't she have to go? Where else could she meet people like the streetside oyster shucker (Robert DuSold) who dreams of being Miss Marple? Or an irritable sculptor (Candy Buckley) and her Spanish gypsy ex-husband (Ken Jennings) with a violently on-again-off-again relationship? Couldn't they all steer her away from her life of humdrum, mass-produced art and into the direction of something that really matters?

Of course they can, of course they do, and of course Mimi Le Duck - ghosts, symbolism, Impressionism, and all - unfolds in all the tired ways you'd expect. Miriam's quest to paint the landscape of her soul might have been groundbreaking before Stephen Sondheim and James Lapine's Sunday in the Park with George, but feels contrived and ordinary enough to be sketched on black velvet. When the edgiest moment involves Golden cramming herself into an avian-cabaret duck costume (designed by Ann Hould-Ward) several sizes too small for her and then claiming it's too sexy for her to wear, something's amiss.

The songs that attempt to derive character development from subjective concepts like form and color tend toward rambling, and themselves bereft of hue; nearly all the numbers have that pulsing, "post-modern" complexity, but are crippled by emotional simplicity that allows them to settle in the ear, but never in the heart. The show itself doesn't look more distinctive, with an ugly set (by John Arnone) resembling a Picasso magazine collage, and staging (by Thomas Caruso) and musical staging (by Matt West) that are all bustle with no sense of visual muscle.

Despite all this, Golden and especially Neville deliver some sweetly sensitive but pedestrian work; a deliciously, satirically strident Buckley and Jennings nicely cover the comic relief. DuSold and Fitzpatrick, who like Golden have been with the show since its original 2004 Fringe Festival incarnation, gamely tackle their roles, but make little impact in them. The same is unfortunately true of Tom Aldredge, who affectionately plays Madame Vallet's timid suitor without the zest for life he needs to believably lure her out of her shell.

Kitt, though, is never on less than glorious display, even when selling for top dollar material that might otherwise be at home in a rummage sale. Her introductory comic showpiece, "It's All About," might be a dumbed-down second cousin to "Moving Uptown," the ballistic comic come-on she introduced six years ago in Michael John LaChiusa's The Wild Party, but her eyebrow-rolling seductiveness is too explosive to resist. And her reflective "All Things New" is a heartfelt, sincere turnaround for the usually artificial Vallet.

But you never see her more clearly than during "Everything Changes" in that dewigging scene. The score's best number, it evokes the conflicting, confusing realities of the past, present, and future as experienced by a woman who's wasted decades pretending they're all the same thing. "The mirror tells the truth," she sings, seeing herself clearly for the first time. The moment, like Kitt's whole performance, is shattering. The rest of the show is, at best, duck under glass.

Mimi le Duck
Running Time: Approximately 2 hours, including intermission
New World Stages / Stage 3, 340 West 50th Street Between 8th and 9th Avenues
Tickets online and current Performance Schedule: Telecharge