CHICAGO -- Thornton Wilder's "Our Town" may well be America's best known play, and turning it into a musical would seem, on first consideration, to be fairly daunting, if not blasphemous. We love the play, revere it even, just the way it is -- this homely saga that recounts the cycle of birth and death in a New Hampshire hamlet so unexceptional yet so truthful in its particulars that it ends up being everyone's home town.

In fact, Wilder steadfastly rejected proposals to set his 1938 drama to music. It was only after his death in 1975 that Wilder's estate relented. To Tom Jones and Harvey Schmidt, the creators of such musicals as "The Fantasticks" and "I Do! I Do!," fell the challenge of giving "Our Town" musical life.

On Wednesday, the result of their collaboration, "Grover's Corners," had its long-postponed world premiere here at Marriott's Lincolnshire Theatre. Half of the musical is lovely, so deeply in tune with its source that you can only wish a rosy future for the show, which after its Chicago run is expected to take to the road. But it's not the half you expect.

Running under 100 intermissionless minutes, "Grover's Corners" acquires its emotional resonance when the action moves to the town graveyard. That's the third act of the play. Before that, we have been introduced to the humble routines of daily life (updated to the between-the-wars era) and witnessed the courtship and marriage of George and Emily, the doctor's son and the editor's daughter. As the actors rearrange a few weatherbeaten props on the bare stage, the stage manager (author Jones himself) lets us know that death is now the subject at hand.

It is the day of Emily's burial and we are on a windblown hill where some of the other deceased townsfolk sit, stalwart statues waiting patiently for the memories of life to burn away and the immortal side of their being to emerge. The scene is stark and it is made starker when Emily, opting to return to Earth to relive one day, realizes how swiftly time goes by, how little people actually look at one another, how spendthrift they all are with the world's riches. "They don't understand, do they," she says flatly, as she regains her place in the cemetery.

This is not the usual stuff of Broadway musicals, and seems to have long been the nub of commercial resistance to "Grover's Corners," which has been in the works since 1983. Reportedly, Jones and Schmidt were often told, "Nobody wants to see a musical in which everyone dies in the end."

As they have structured the scene, however, with a series of haunting melodies and simple lyrics that only occasionally degenerate into the simple-minded, the climax to "Grover's Corners" proves immensely moving. The show opens up like a beautiful night-blooming flower, thousands of little stars come out overhead and, in the swell of voices, acknowledging the terrible and splendid experience of life, the musical seems in full harmony with "Our Town."

The problems come earlier. Although Jones and Schmidt have long celebrated homespun sentiments and the joys and heartache of young love, they are less successful this time in establishing the very ordinariness of Grover's Corners. The point of the play is that nothing much ever happens here -- or rather that the rituals are the rituals of millions of households, where having breakfast, packing the kids off to school, shelling beans on a back porch and going to choir practice of a Sunday evening constitute the fabric of living.

Such numbers as "Our Town," "A Hearty Breakfast" and "Snapshots, Photographs" tend to describe the characters and their ways without supplying that extra illumination that makes the common uncommon. The impressionistic vignettes don't connect and they make for a perfunctory overview: Here's the paper boy, there's the drunken choir director, and, oh yes, that's the whistle of the train, so regular you could set your clock by it.

We seem to be marking time until George and Emily (Michael Bartsch and Deanna Wells, and both as fresh as spring water) wander into the drugstore after school and realize over sodas that they are in love. Jones and Schmidt have written one of their sweetest ballads, "I Only Want Someone to Love Me," for the occasion, after which the two sweethearts undertake -- with puppy-dog spirits and a suggestion of Fred and Ginger abandon -- the show's only dance number. Barely winded, they pause to gaze into one another's eyes and then reprise the beautiful song.

The eternal round of love and marriage is gearing up all over again. "One in a thousand times it's interesting," comments the stage manager. Theatrically speaking, though, what "Grover's Corners" has suddenly found is a kind of linkage that eludes it at the outset. The plain characters, the heartfelt music, the timeless sentiments and even the wry presence of the stage manager intertwine naturally and fluidly, giving the show a momentum that carries through to the starlit ending.

Jones functions well enough as the stage manager, although he doesn't have the presence that an accomplished actor (Hal Holbrook, say) might lend to the part. Schmidt also appears on stage at an upright piano, singing along with the chorus, which satisfies the demands of equal billing perhaps, but seems an expendable arrangement. Otherwise, the cast is true to the self-effacing but dignified populace Wilder chronicled, and their voices are, singly and collectively, impressive.

Their task is not made easy by an adaptation that, by compressing Wilder's script, tends to treat the residents of Grover's Corners as archetypes. Take the exquisite Linda Stephens (who appeared for years in Washington at the Harlequin Dinner Theatre as Linda Shue). That she finds in Mrs. Webb a certain officiousness along with the warmth, a tremulousness in the apparent strength, a radiance in the despair, is a tribute to the actress, who, like most of the performers, is provided with relatively few opportunities to explore the detailed humanity that makes "Our Town" so enduring.

Musicals abridge, perforce. But for its first 40 minutes, Grover's Corners is a sketchy place, inhabited by sketchy people, and director Dominic Missimi seems unable to anchor it to the stage. It is the weight and solemnity of death that lodges it in your heart. Even a last-minute failure of lyric inspiration in "Goodbye, World" (Emily is obliged to sing that title refrain 18 times by my count) cannot destroy a sublimely touching leave-taking.

"Grover's Corners" has no trouble dealing with the cosmic implications of Wilder's fable. Strange that it should flounder on what is seemingly safer ground -- where proud, upstanding people raise families, exchange gossip and dream about the trip they'll never take to France.

"Do Not Hold On," the chorus of the dead urges, as Emily ventures back to Earth. But "Grover's Corners" never really shows us what was slipping through her fingers then and will do so all over again -- this time forever.

Grover's Corners, based on "Our Town" by Thornton Wilder. Book and lyrics by Tom Jones; music, Harvey Schmidt. Directed and choreographed by Dominic Missimi. Musical direction, Kevin Stites; orchestrations, David Siegel. Sets and lighting, John and Diane Williams; costumes, Nancy Missimi. With Tom Jones, Harvey Schmidt, Deanna Wells, Richard Henzel, Linda Stephens, Michael Bartsch, Les Hinderyckx, Sharon Carlson, Renee Matthews, James Harms. At the Marriott Lincolnshire Theatre in Chicago, through Sept. 11.