When Tom Mullen decided to put together a tribute to Gene Kelly's work -- a revuesical, if you will -- he planned something fun, light and energetic. But a dramatic element changed the entire direction of the show.

When "What a Glorious Feeling" makes its world premiere at Mason Street on Wednesday, audiences will glimpse the story behind Kelly's long collaboration with filmmaker Stanley Donen and dancer/choreographer Jeanne Coyne.

The filming of "Singin' in the Rain," arguably Hollywood's ultimate musical and easily the apex of the trio's careers, was a natural setting for the play.

You might think of them as filmmakers or dancers, "but they were so much more," said Mullen, a choreographer in his own right as well as Mason Street Warehouse co-producing director.

Kelly, a dancer, actor, director, singer and choreographer, and Donen, a producer-director-choreographer who started as a Broadway dancer, were a formidable pair. They co-directed the musicals "On the Town," "Singin' in the Rain" and "It's Always Fair Weather," reinventing musical films along the way by making the songs part of the story while fully exploiting Kelly's athletic approach to dance. Donen directed "Take Me Out to the Ball Game," "Royal Wedding," "Give a Girl a Break," "Seven Brides for Seven Brothers" and "Funny Face." His long collaboration with Kelly came to a screeching halt shortly after Donen married Jeanne Coyne, Kelly's assistant.

By the time Kelly and Donen co-directed "It's Always Fair Weather," the formerly close friends weren't speaking. Donen and Coyne married in 1948 and divorced in 1949; she married Kelly in 1960 and died in 1973; Kelly died in 1996.

"She was the woman they both loved," Mullen said. "She was a student of Gene's since she was 14. He was very paternal. Sure, it was extremely difficult for Gene to watch."

Mullen commissioned Jay Berkow to create the book after seeing Berkow's writing and directing skills in the popular off-Broadway play, "Jolson and Company." (Coincidentally, Gene Kelly's dad was Al Jolson's manager.)

"I thought he did an amazing job getting these characters fully realized," Mullen said.

Mullen and Berkow began reading everything they could on the trio, including biographies written by Donen, Kelly and Betsy Blair, Kelly's first wife. Each tells the story a bit differently.

"You didn't know who to believe," said Mullen. He and Berkow invited Donen to be involved, but "in a word, he said it would be too painful an experience to relive," Mullen said.

The play's framework sets all events in the context of the filming of "Singin' in the Rain," the story of two song-and-dance partners who break into Hollywood at a time when the film business is making a somewhat painful transition from silent movies to those with sound.

The dashing Don Lockwood (Kelly) becomes a star; his partner Cosmo Brown (Donald O'Connor), like Donen, ends up working behind the scenes. Kathy Selden (Reynolds) is the no-nonsense young woman Lockwood falls for and eventually wins.

"Cosmo constantly complains that he came up with the ideas and no one credits him. He never gets the girl," Mullen said.

The play truncates much of the real-life drama even as it celebrates Kelly, Donen and Coyne's technical and artistic brilliance. (Coyne's credits always list her as an assistant; Mullen said she was skilled at translating Kelly's work into individual steps and teaching them to other dancers.)

"We also take great liberty with the timeline," he said. "A lot of this happened over a lot of time."

The play will include skeletal renditions of songs and dances so closely identified with Kelly.

"It's a fragmented version of the numbers," Mullen said. "You're so familiar with them, to seem them deconstructed is really cool."

Kelly's reputation as a charismatic and sweet guy-next-door is tempered by his intensely competitive and perfectionist nature.

"Kelly had a great ability to take real-life situations and use them in a somewhat cruel way," Mullen said, citing the plot of "Singin' in the Rain" and behind-the-scenes tension as a perfect example.

The competitive spirit may well come naturally to Broadway veterans Sean Martin Hingston ("Contact"), who plays Kelly, and Michael Gruber ("Swing!," "Kiss Me, Kate," "My Favorite Year") as Donen. Colleen Dunn ("Contact," "Sunset Boulevard") plays Jeanne Coyne. Newcomer Brynn Curry was cast to type; the 20-year-old student has a small role as the young Debbie Reynolds. Gordon "Bud" Thompson fills out the cast in dual roles as producer Arthur Freed and legendary director-choreographer Busby Berkeley.

"Michael, Colleen and Sean have a 15-year history, a long history," Mullen said, adding that Hingston and Gruber have often auditioned for the same roles in New York productions. "They are extremely competitive. Sean has that demanding perfectionist streak."

The cast started rehearsals in New York with choreographer Jamie Rocco, whose credits include 25 productions of "Singin' in the Rain." Gruber will definitely get a new perspective on the work; he's played Kelly's role in 15 theater productions.

"There's no doubt about Kelly's genius, but it came with a hefty price," Mullen said. "He really hurt a lot of people."

Whether Mullen and Berkow succeed in presenting all sides of the notable triangle remains to be seen. Mullen said a world premiere in Saugatuck gives the company the freedom to "play and fall on our faces." But co-creators are open to criticism. Mullen is hoping to lure a "Variety" reviewer to the show; it would be another first for Mason Street.