Forget dust-ups between cowmen and farmers and the dubious existence of that surrey with the fringe on top: The real impediment to romance in the "Oklahoma!" now at Wolf Trap seems to be a black rocking chair. When the stubborn heroine, Laurey (Amanda Rose), and other characters listlessly plop into it during early sequences set outside Aunt Eller's weather-beaten cabin, the chair starts to symbolize the intermittent sluggishness of the production, which is based on the "Oklahoma!" that hit Broadway in 2002. It may be a beautiful mornin' and all, but as the nonmusical scenes in this revival crawl along, one gets a sinking feeling that Laurey may not make it to the much-hyped social with cowboy Curly, farmhand Jud or anybody else.

Fortunately, no amount of torpor in the staging can ruin Richard Rodgers's melodies, and this touring production does perk up when it soars into such classic tunes as "People Will Say We're in Love." And when the ditzy Ado Annie (Sarah Shahinian) belts out "I Cain't Say No," or when strings and woodwinds break into a brooding dirge at the start of Jud's solo "Lonely Room," the music -- overmiked as it is -- carries the show along.

That's just as well, since most of the performers don't quite have the pizazz to energize proceedings by themselves. Tom Lucca's menacing Jud injects a dose of sinister intensity whenever he strays onstage, and Brandon Andrus has a relaxed, puppyish charm as Curly, but in general the cast members are merely passable actors. Though she has a sweet, strong soprano and a graceful dancing style, Rose in particular falls short in the charisma department, her oddly deadpan Laurey making it hard to care whether she winds up with the good guy or the bad.

In fact, it's not an individual personality but a collective one -- the no-nonsense frontiersmen and women in their cowboy hats and gingham -- that hits the high-water mark for zest. As directed by Fred Hanson (Trevor Nunn directed the Broadway version), the show displays more energy when a two- or three-person scene (such as the almost interminable opening) gives way to a bustling crowd -- especially a crowd that starts hoofing. Ginger Thatcher has re-created the choreography of showbiz powerhouse Susan Stroman ("Contact," "The Producers"), and the dancing has a delightfully idiosyncratic, asymmetrical verve. In case you've forgotten, everything is up to date in Kansas City, and in the zippy number that's a paean to that metropolis, the comic Will Parker (Daniel Robinson) and his peers do a mean caper with some lassos. And in the psychologically freighted dream ballet that ends Act 1, threatening male and female figures conjure up a nightmarish Wild West while wielding chairs that evoke a sleazy barroom.

Such ensemble sequences provide a welcome respite from this production's deliberately stark aesthetic. None of the technicolor cutesiness of the movie here. Aunt Eller's cabin sits near a ramshackle windmill on a desolate prairie, with the backdrop's sweeping semicircle of sky somehow suggesting the curve of the Earth as seen from outer space. When things get really dicey for the characters -- during Jud's cameos and the frontier-justice cliffhanger in Act 2 -- the sky seethes with melodramatic dark clouds.

The effect of the meteorology, and of the scenic spareness in general, is to give this much-loved musical a surprising touch of existential angst. No wonder the action sometimes seems to bog down: Sit in that black rocking chair and you might stop thinking about surreys and hampers stuffed with gooseberry pie and start contemplating the loneliness of the human condition.

Oklahoma! Music by Richard Rodgers, book and lyrics by Oscar Hammerstein II, based on the play "Green Grow the Lilacs" by Lynn Riggs. Directed by Fred Hanson. Choreography by Susan Stroman, re-created by Ginger Thatcher; set and costume design, Anthony Ward; lighting, David Hersey, adapted by Ted Mather; sound, Brian Ronan. Based on the Royal National Theatre/Cameron Mackintosh Broadway production. Through tomorrow at Wolf Trap's Filene Center, 1551 Trap Rd., Vienna. Call 703-218-6500 or visit www.wolftrap.org.

Saved by the songs: Pat Sibley, left, Brandon Andrus and Amanda Rose in Wolf Trap's scenically spare staging of "Oklahoma!" based on the 2002 Broadway production.