Gideon died May 1 at his West Hollywood home of complications from colon cancer, said Bernard Vyzga, his longtime companion.
Usually performed by a man and a woman playing two single strangers, the musical revue "Marry Me a Little" was re-conceived by Gideon as a two-man show. It debuted in 1999 at the tiny Celebration Theatre in Hollywood.
"The concept of romantic love is so much a part of gay culture, I thought, why not put two men in it," Gideon told the New York Times in 1999. "I never thought Sondheim would allow us to do it."
At the time, Sondheim said he did not want to comment on why he approved the change.
In the musical, Gideon and Craig Curtis played characters in adjacent apartments who express lonely yearning in songs that Sondheim wrote for other shows but never used. The Los Angeles Times review pronounced the production "deft" and said some of the songs "never sounded truer . . . or more affecting."
According to his http://ttp://web.me.com/gideonman/Steve_Gideon_Website/HOME.html, Gideon believed he was best known in Los Angeles for "Naked Boys Singing," a musical revue that was true to its title when the Celebration presented it in 1998.
Calling the show "devastatingly amusing," the Times review praised Gideon's beautiful delivery of a monologue that wistfully addressed lost love. It also pointed out that the performers were "triple threats, whose singing, dancing and acting skills are first-rate."
He was born Stephen Craig Hayes on Nov. 13, 1956, in Richmond, Va., to Luby Hayes, a home-improvement salesman, and his wife, Ruby, who worked in hospital billing.
While in high school in North Carolina, Gideon performed with a local theater group and was a radio DJ.
At Harvard University, he appeared in 14 theatrical productions but majored in government. The day he received his bachelor's degree in 1979, he joined a touring musical revue, "The All Night Strut!"
Patty Woo, who appeared with him in Harvard shows, recalled that Gideon was "clearly deeply gifted, even back then. He was cast as Jesus in 'Godspell,' as a freshman no less."
He also attended the Boston Conservatory of Music.
About two decades ago, Gideon moved to Los Angeles.
His other projects included the film noir parody "Nite Club Confidential," which he performed locally into the 1990s, and his 1995 CD "Feels Like Home," which included two original compositions.
His sister, Pam Poole, said he was disciplined and caring, a comedian who would be on "if you wanted to be his audience."
In addition to his sister and his companion, Gideon is survived by his father and his brother, Ronald.
A memorial will be held at 10 a.m. May 17 at the Village at Ed Gould Plaza, 1125 N. McCadden Place, Los Angeles.
Memorial donations may be made to the West Hollywood Recovery Center, www.thewhrc.org.