Earlier this month on Dec. 3, an opera lost for more than 60 years returned to the stage. "De Organizer," by jazz pianist James P. Johnson and poet Langston Hughes, had one performance at Carnegie Hall in 1940 and then it disappeared. But, the vocal music was discovered five years ago and a painstaking reconstruction of the orchestral score made the performance possible.

James P. Johnson was an important figure in American music. He's called the father of stride piano, a style of playing distinguished by the striding movement of the left hand which walks back and forth, playing a note in the bass followed by a chord in the middle register. He taught Fats Waller and Willie "The Lion" Smith. Hao Huang, a music professor at Scripps College who specializes in jazz, says James P. Johnson's influence was widespread.

Duke Ellington, Count Basie, Fletcher Henderson, they all listened to his piano rolls, and especially in their early work, you can hear a very strong influence. He was such an important musician of the time.

James P. Johnson was also an accomplished composer of popular music. In fact, he wrote the Charleston, a melody that ended up defining an era.

What many jazz buffs don't know is that, beginning in the 1920s, Mr. Johnson started to write symphonic music as well. Among his concert works was a one-act opera called "De Organizer" that he wrote with poet Langston Hughes.

The opera has been lost since its premiere in New York, and musicologists have been looking for it ever since. Colorado Symphony conductor Marin Alsop says not only was it written by two of the leading African-American artists of the time, it was also based on a political theme: labor organization.

"I mean, it's not just an opera; it has all these other, wonderful social dimensions to it," he said. "And that's why, of course, we were extremely curious about the piece and anxious to try to find some scholarship and some history on it."

Apart from Langston Hughes' complete libretto, only one piece survived from the opera, "The Hungry Blues." Mr. Johnson recorded that tune with a studio band in 1939, one year before the Carnegie Hall performance. Ms. Alsop says, based on that one piece, musicians have often said "De Organizer" could be Johnson's greatest achievement in concert music.

Maestra Alsop is one of dozens of musicians who have searched for this score. The hunt ended in 1997, when some of Eva Jessye's papers were unpacked at the University of Michigan. Ms. Jessye directed the choir for the original Broadway production of "Porgy and Bess" in 1935. She also led the chorus for "De Organizer"'s Carnegie Hall debut. No one realized, though, that the lost opera was among the papers she'd bequeathed to the school until music professor James Dapogny happened to see a small book casually resting inside a glass display case.

"I don't think the people who put it on display knew that it represented this legendary lost work of art," Mr. Dapogny said.

Professor Dapogny says his knees buckled when he saw it, and he was overwhelmed when he finally held the music in his hands. The good news was every sung note was there. The bad news? There were no instrumental parts, not even music for rehearsal piano. So, Professor Dapogny called Barry Glover, James P. Johnson's grandson, to ask if he had any information about the missing music. Mr. Glover says he was excited when he heard the score had been found.

"Stunned is putting it mildly. I was almost beside myself, because I had stumbled on the limited amount of material that we had on 'De Organizer' a couple years prior to that," he said.

The sketches Barry Glover found covered just over 25 percent of the music in the entire opera. After collecting these and as much other material as he could, James Dapogny started reconstructing the orchestral score, including 80 measures that were completely missing. When more musical sketches turned up later, he found that the harmonies he had written almost exactly matched James P. Johnson's originals. "You know, harmonically, it's not much of a mystery. But when I found the sketch...I sort of had the harmonies right, but the textures were wrong. And of course, there's no way to guess at those," he said.

Professor Dapogny worked on the opera for several years before taking it to the University of Michigan's music department to start arranging a performance.

The plot for "De Organizer" is very simple. A group of sharecroppers gather in a cabin, awaiting the arrival of a union organizer. They commiserate about their troubles, until at last, like a mythic hero, 'de organizer' enters and starts urging them to form a union.

Susan Duffy, author of the book The Political Plays of Langston Hughes, says the Organizer's speech is similar to a sermon, and the opera itself resembles a religious service.

"By the end of the play, you have the sense that it's designed to have the audience on their feet singing, 'Fight, fight, we've organized a union here tonight,'" she said.

Ms. Duffy said the opera is a great example of Langston Hughes' "blues" poetry, strongly influenced by rhythmic figures and musical phrases. The rebirth of "De Organizer," she says, will give scholars a chance to reexamine the poet's theatrical work.

"I think his stature as an American poet and social critic is certainly undeniable and well deserved, but he remains virtually unknown as a dramatist of any kind of literary importance in the American theatre," she said. "And I think in examining his plays, the ones that I examined were very powerful."

Langston Hughes was deeply involved with the radical left during the 1930's and had written a number of political plays. That may be why James P. Johnson approached him about collaborating on "De Organizer."

Musicologist Hao Huang says Mr. Johnson probably thought Langston Hughes, who was closely associated with the Harlem Renaissance, would bring a tone of seriousness to the project.

"I think that he was trying to cross over into the concert halls, to bring black music out of the sporting houses and nightclubs into concert halls," he said. "And I think that fits very much into the whole Harlem Renaissance ideal of the New Negro as someone who's going to create a new high culture for black people."

Although the finished piece is not exactly what the audience heard in Carnegie Hall in 1940, James Dapogny says it's pretty close, and James P. Johnson's music is beautiful.

"Of course the nightmare I have in mind is that somebody will turn up the score and find out that I did it completely wrong," he said. "And honestly... I mean, I may be overstating this... but honestly, I think if James P. Johnson heard what I wrote, he'd be perfectly happy with it."

"De Organizer" was performed for the first time in more than 60 years with University of Michigan students onstage at Orchestra Hall in Detroit. James Dapogny says he's already received a number of calls from other conductors, hoping to perform the work in other venues throughout the United States.