"Movin' Out," Twyla Tharp's full-length ballet to the music of Billy Joel, presents just such a puzzle. The thin, stereotypical plot involves the lives of some working-class kids - characters from Billy Joel's songs, actually - who have just graduated from high school. There's slutty Brenda and good-girl Judy, tough-guy Eddie and athletic Tony. Brenda breaks up with the former and flirts with the latter. Meanwhile, Judy accepts an engagement ring from high school sweetheart James, to the strains of "Just The Way You Are." The Vietnam War intrudes into these couples' playful lives, and the men go off to fight. James is killed. Tony and Eddie are messed up. Can Brenda and Tony find their way back to each other? Can Eddie find his way back to himself? "Who," as Eugène Ionesco said in "The Bald Soprano," "has any interest in prolonging this confusion?"

Dance isn't the best medium for narrative, and this particular story has been told a thousand times. You watch not because you care about these stock figures, but because they're pure Americana. And, of course, they dance.

On a certain level, this show is brilliant entertainment, from the pulse-quickening music (given a first-rate performance by the "Movin' Out" band and pianist/vocalist Darren Holden) to the energy of the dancers. Tharp routinely demands the impossible, and the results are mind-boggling. At first, the overall effect is of being at a rock concert with extraordinarily sophisticated visuals. It's exhilarating. You feel as if you're thrashing around in a psychedelic washing machine, devoid of thought, blind to everything but sound, movement and rhythm.

By intermission, I was dazed by song and color, uninterested in the plot but still dazzled by the overall production. But my companions - both serious dancers - were less impressed. They applauded the athleticism of the dancing, but disliked its presentational style, the unabashed way the dancers preened for the audience after almost every showy move. They found the choreography unidimensional and unsubtle. "It's also cluttered," said one. "There are too many steps." They did agree, though, that there was one moment they liked: a scene in which a barefoot Vietnamese woman moved among the uniformed soldiers like a wraith.

There's a feeling you sometimes get when an actor, dancer or musician is performing beautifully. It's a kind of yearning, something very close to love. It isn't personal - it's because the performer has become a conduit for the transcendent possibilities of the art form itself. But "Movin' Out" is not the kind of art you enter; it's art to be watched from the outside. If it's art at all.

Which is not to say that these aren't amazing dancers or that the production doesn't have some stirring moments. I liked the two pas de deux between Laurie Kanyok's Brenda and Corbin Popp's Tony, with Popp's power and Kanyok's live-wire energy; Matthew Dibble's classicism as James; the leaps and whiplike turns of Ron Todorowski, playing Eddie. There were also two particularly lovely dancers in the ensemble: Alice Alyse and Kristine Bendul.

Thinking about the show later, though, I realized the predominant emotion it communicates comes not from the dancers, but from Tharp herself. And for the most part, that sensibility is fast, horny and in your face.

Performances don't end when the curtain falls - or, in this case, after a prolonged and shamelessly milked curtain call. They continue in your head. And it turned out that even if I hadn't entered "Movin' Out," it had entered me. I awoke the next morning still thinking about it. I wanted to go back and see it again. I thought perhaps I'd missed something tricky in the steps, something that tied everything together, something that imparted depth.

So here's the critical stamp I'd place on "Movin' Out": sensory pleasure; a lingering, ambivalent aftertaste.

"Movin' Out" opened on Broadway in October 2002 to acclaim, and it's still running. Now the first national touring edition, scrupulously supervised by Tharp, is also winning praise.

The tour cast, Tharp notes, features "six dancers who each have a year and a half in the Broadway show under their belts, and they're great." And such Joel chartbusters as "Big Shot," "Uptown Girl" and "We Didn't Start The Fire" are belted out from the stage by Darren Holden, former understudy for the show's Broadway vocalist, Michael Cavanaugh.

A work of stunningly gymnastic physical virtuosity and visceral passion, "Movin' Out" is performed by prime, ballet-trained dancers and resembles no other big rock musical. Yet its success won't surprise fans of Tharp, a rigorous innovator who, in her 40 year-plus career, has devised some 125 dances to music ranging from Mozart to Frank Sinatra and the Beach Boys, for the Joffrey Ballet and American Ballet Theatre as well as her own companies. She also staged and choreographed Broadway's "Singin' In The Rain" years before winning a 2003 Tony for her breathtaking "Movin' Out" dances.

Initially, though, theater insiders expressed skepticism about a serious, non-revue musical based on Top 40 hits by a mainstream pop tunesmith.

Did the chatter rattle Tharp? "I think long ago I learned to stop listening to folks saying what I don't want to hear," she replied by phone from Manhattan, in typically succinct, confident fashion. "I also learned something early on about music. Whatever it's called, whatever genre it's parked in, classical or pop or jazz, it's either good or bad. End of story."

Tharp didn't let negative reports drifting out of Chicago, during a pre-Broadway tryout of "Movin' Out," faze her either.

"I knew there were problems. This was a different kind of show, and we were trying to split the difference between a musical and a rock concert. Originally, it was confusing for people. At first we had a more cinematic opening for the show. But in the theatre, the audience is used to being given an introduction to the characters at the start."

Tharp quickly made adjustments. By the time "Movin' Out" reached New York, the five main characters (three male Long Island pals and two women who love them) were clarified. And Tharp's generational saga of lost and found love, of life-altering Vietnam combat experiences and their bittersweet aftermath, came across potently - without a word of dialogue spoken.

The show has been a victory for Tharp and for Joel - who swiftly gave it his blessing, and shared a Tony honor (with Stuart Malina) for its orchestrations.

Long a Joel fan, Tharp said she has often played his tunes during her daily morning workouts. "He not only writes good, what we call, rock and roll, but he's also a very good storyteller who has an extreme attention to detail, and is very specific about scenes and characters," she commented.

But while the catchy odes conjured up images of love, war and social change in Tharp's mind, she knows people come into "Movin' Out" with their own associations.

"Some of the stage action takes advantage of the emotional baggage everyone brings to Billy's music," Tharp explained. "Sometimes I departed from that. With the song 'She's Got A Way,' I realized what I needed to have it say ran counter to what Billy meant the song to be. But he told me to go for it."

Did he like the final result? "He saw a rehearsal, and cried," she said, with a light chuckle. "Crying - always a good sign."

The initial version of "Movin' Out" was finished September 10, 2001. Tharp acknowledges it may move spectators to tears now for reasons she couldn't have anticipated.

"What I wanted to do was history, like the 'Living Newspaper' shows from the 1930s based on nonfictional thematic material, on subjects like electricity, water, housing. I said, 'OK, I'll do war.' When the war in Iraq started, I said, 'Here we go again.' "

Since 2000, Tharp has been making concert-dance works for a small company, Twyla Tharp Dance, which has performed here and across the country. Has she started filling boxes for an upcoming creative venture?

Her reply was crisp, and pure Twyla. "Yes, but I don't talk about the future. I like doing a lot of different things, and trying to do them well."

"The working title is "Good Career Move." It's about the music business. I'm going to take it apart. What Mel Brooks did to Broadway in "The Producers," I'll do the to the music business."

Joel said all the songs will be original, and that he might collaborate with other composers on some of the songs.

"Movin' Out" has been an unexpected hit on Broadway since it opened in 2002. It plays through June 20 at Seattle's Paramount Theatre, as part of its first national tour.

In trailblazing a form - is it ballet or musical? - Tharp continues her practice of morphing the courtliness of classical ballet into exuberant modern quicksilver. Her dancers move with surprising abandon. Alongside the rigid upright turns and toe shoes are tennis shoes and doses of karate, dirty dancing, Texas two-step, the Moonwalk and gymnastics.

The dancers in the first cast (Wednesday evenings and Saturday and Sunday matinees) are stunning. There's the leggy, sinuous Holly Cruikshank as Brenda and coiled-up powerhouse Ron Todorowoski as Eddie. Tony is smooth, sultry David Gomez.

"Movin' Out" barely has scenery - it is a two-level stage with the band on top and minimal movable props below. But it does have bright lights, a central love story and big production numbers with an ensemble of dancers.

When fallout from the war sends Eddie to drugs and Brenda and Tony to other lovers, heroin and jealousy transform into show-stopping dance. Brenda and Tony sizzle. When they return to each other, it is with death-defying lifts and turns in tight, desperate embraces to the bluesy song "Shameless."

Tharp chooses Joel's best songs, many of which are seldom broadcast, including "Summer, Highland Falls," "Goodnight Saigon" and "I've Loved These Days." There are a few selections from his 2001 foray into classical composition, and radio hits such as "Scenes From An Italian Restaurant," "It's Still Rock and Roll To Me," "Pressure" and "Uptown Girl."

Joel has yearned to belong uptown since his early days pilfering Beethoven melodies for pop songs. Tharp sees him instead as a great writer for Broadway. He provides the broad strokes, she provides the shading. Their pas de deux expresses one good, true American period, in high American style.

"Movin' Out" is invigorating, thanks to the unstoppable dynamism and shrewd eclecticism of Tharp's Tony-winning choreography, the excellence of the dancers, and the driving power of a killer stage band, fronted by keyboard player and vocalist Darren Holden on opening night. (Matt Wilson sings Joel's tunes at alternate performances.)

Tharp's wall-to-wall dances don't mimic any other rock musical's. Her movement vocabulary adroitly incorporates rock and ballroom steps, ballet positions, jazz thrusts, karate kicks, along with gestures, dips and leaps you could swear you've spotted in old Cyd Charisse movie musicals, and "West Side Story."

The male dancers here get to channel both Bruce Lee and the young Mikhail Baryshnikov. Especially exciting are the jumps, leaps, back-flips and corkscrew pirouettes of hyper-athletic Eddie. The women, particularly the sexy Brenda, get to be go-go dancers, ballerinas and Rockettes.

Though the movement scheme can get repetitive, "Movin' Out" actually gathers power and texture in its second act. Dance turns out to be a perfect medium for the visceral, inchoate rage Vietnam vet Eddie expresses in the "Prelude/Angry Young Man" sequence. And the inability of Tony to reconnect with Brenda turns their "Big Man On Mulberry Street" duet into a highlight. (Their tentative, then ecstatic make-up to "Shameless," is another high.)

"Movin' Out" demands first-class dancers, and two alternating casts. In the Paramount's opening-night ensemble, the leggy, super-supple Broadway veteran Holly Cruikshank as Brenda and David Gomez's rangy Tony were perfectly matched, and Julieta Gros shone as the glowing and grieving Judy. Though not as magnetic an Eddie as Broadway's Tony-nominated John Selya, Ron Todorowski is a terrific mover, a spinning and soaring wonder. In a smaller part, Matthew Dibble made a fine James.

Tip: Read the program's plot synopsis before the show starts. Though the mood of Joel's songs match Tharp's tale, the lyrics don't tell the whole story.

"Movin' Out" places rousing singer/pianist Darren Holden (Matt Wilson on some nights) and a rowdy band above a stage full of limber dancers gyrating to cover versions of Maestro Billy's musings. Director Tharp has concocted a wordless story line of sorts - something about a group of friends in the '60s, their broken relationships, and the Vietnam War - but the effect mostly resembles those random videos you can't make heads or tails of when you're drunk and watching the karaoke screen in a neighborhood bar. A sincere pas de deux to "Just The Way You Are" must surely be the definition of middlebrow entertainment. Worse, Tharp's attempts to squeeze some depth out of Joel's "heavy" later hits only make their ersatz grit sound even phonier: The Vietnam flashbacks look a bit like the Max Fischer Players from "Rushmore" invading the set of "Solid Gold"; no amount of dry-ice can turn "We Didn't Start The Fire" into meaningful social commentary.

Is Tharp nuts? Well, if she is, her troupe refuses to acknowledge it. The level of athletic grace from the entire gorgeous ensemble is frequently astonishing - people rush on, leap toward the ceiling, and seem to float for a second or two. As Eddie, the suffering sweetheart introduced in "Scenes From An Italian Restaurant," an electrifying Ron Todorowski spends the evening doing what is best described as acrobatic ballet and, man, it sends your heart jumping right up into your throat and keeps it knocking around in there. I don't know what The New York Times' Ben Brantley was smoking when he called this show "a shimmering portrait of an American generation," but if you can get your hands on some of it, hey, live it up while Todorowski and company blow your mind.

"Movin' Out" creators Billy Joel and Twyla Tharp won Tony Awards for orchestrations (with Stuart Malina) and choreography, respectively. The show, opened October 24th, 2002 on Broadway, launched its National Tour from Detroit's Fisher Theatre, January 27th, 2004. James L. Nederlander, Hal Luftig, Scott E. Nederlander, Terry Allen Kramer, Clear Channel Entertainment and Emanuel Azenberg produce.

The bookless show, currently residing at Broadway's Richard Rodgers Theatre, uses Joel's song lyrics and Tharp's choreography to tell the story of six friends and lovers across three decades through love, war and loss. There is no dialogue and all songs are performed by the pianist-singer, who sings non-stop and heads an on-stage band during the show.