When "Singin' in the Rain" opens at the Paper Mill Playhouse Wednesday, what the audience won't see is the famous movie reproduced on stage.

What they'll get instead, says director and choreographer James Rocco, is an attempt to do on stage what the authors did on film -- tell a story about the joys and challenges of performing. The Betty Comden-Arthur Freed tale concerns silent-film stars trying, with uneven success, to make the transition to talkies.

The show's evolution reverses the usual process: The MGM film with Gene Kelly and Jean Hagen -- "arguably the best movie musical of all time," Rocco says -- came first, in 1952, followed by the stage interpretations, the first important one in London about 15 years ago. That production's success was not repeated on Broadway, where the show was greeted with disappointment.

Although Rocco says he has been enamored of "Singin in the Rain" since he was a child, his professional association with it began about a decade after it fizzled in New York. "About three years ago," he said from his home in New York City, "[choreographer] Linda Goodrich and I were asked to do this show for theater. I had always been intrigued by it. From the moment I watched it as a little boy, I always thought it would work -- I had a clear picture of how it could work as a stage musical."

He and Goodrich took on the project at the Music Theater of Wichita and, about 18 months later, at the Sacramento Light Opera. "Both times," Rocco said, "it was wildly successful. Audiences were crazy for it."

In those productions, he said, he and his colleague concentrated on what story Comden and Green had intended to tell when they wrote this show around a catalog of popular songs by Nacio Herb Brown and Arthur Freed. "The movie is one thing. The stage is another," Rocco said. "They are different animals; they move in different ways. ... But we kept trying to get to the core of what the original authors intended and we came to the conclusion that it was about performing, not about the movies.

"Then it flowed out of us. We saw it as a Fifties musical like some of those by George Abbott -- 'Damn Yankees' and 'Pajama Game.' Yet in some ways, it's more intimate ... I think where people went wrong before is that they treated it like '42nd Street,' with one ensemble blockbuster after another. This is a story about four people, and every once in awhile it explodes with a giant number. It's the best of both worlds."

Those explosions include the title song, "You Are My Lucky Star" (written for the movie "Hollywood Revue of 1929"), "Good Mornin'," and "Make 'em Laugh," which became a signature for Donald O'Connor, who performed it on the screen.

And will it rain onstage during the title number?

It will.

From Rocco's point of view, it has to.

"The moment when Kelly is swinging from a lamppost at the end of 'Singin' in the Rain' -- to me, it's iconic. It's not 'Singin' in the Rain' without that," Rocco said. "It doesn't even matter if it's Gene Kelly. It's the thought of hanging from a lamppost and standing in the rain, full of love, the rain washing you of your past, all that that connotes. That's an important moment for us to accomplish."

Playing the Kelly role of silent movie idol Don Lockwood is Michael Gruber, who appeared on Broadway in the original companies of "Miss Saigon" and "My Favorite Year." Deborah Jolly, who played Theresa in the ABC serial "Loving," stars in the Jean Hagen role as Lockwood's leading lady, Lina Lamont, whose voice could shatter glass. Christina Saffran plays Kathy Selden, the young actress hired to dub Lamont's voice for the talkies, and Randy Rogel plays Cosmo Brown, Lockwood's sidekick and former vaudeville partner. Gruber, Saffran, and Rogel played these parts in the Sacramento production, and Saffran played Kathy Selden on Broadway.

The company has shot four short silent movies to be used in the production, "to get the point across," as Rocco puts it.

As for the downpour, Rocco said the Paper Mill's staff has accepted that challenge with glee. "The technicians that work there are such artists themselves that they get a kick out of seeing how far they can push themselves. You know, there are people out there who specialize in doing things like making it rain. The Paper Mill staff have consulted with those people, but they're not going to bring them in to do 'Singin' in the Rain' because they want to accomplish it themselves."