This was the fourth time the song “Singin’ in the Rain” was used in an MGM film. It was introduced in The Hollywood Revue of 1929 (1929) when it was sung by the MGM roster in front of a Noah’s Ark backdrop. Jimmy Durante sang it briefly in Speak Easily (1932). Judy Garland also sang it in Little Nellie Kelly (1940). Durante was the first to add the often used “Doo Doo Doo” and “Ya Da Da Da” to the song.
Although uncredited, Gene Kelly had two incredibly talented choreography assistants. These ladies were none other than Carol Haney (“The Pajama Game”) and Gwen Verdon (Broadway star of “Can-Can”, “New Girl In Town”, “Damn Yankees”, “Redhead”, “Sweet Charity” and “Chicago”). In fact, Kelly’s taps during the “Singin’ In The Rain” number were post-dubbed by Verdon and Haney. The ladies had to stand ankle-deep in a drum full of water to match the soggy on-screen action. Gene Kelly had also recommended Carol Haney for the role of Kathy Selden.
Howard Keel was the original choice to play Don Lockwood; however, he was replaced by Gene Kelly as the screenwriters evolved the character from a “Western actor” background to a “song-and-dance vaudeville” background.
Very early on in the pre-production stage, Judy Garland, June Allyson, and Ann Miller were considered for the role of Kathy Selden, but all were considered “too old”. Jane Powell and Leslie Caron were also briefly considered before Debbie Reynolds (then a newcomer) was cast.
Donald O’Connor admitted that he did not enjoy working with Gene Kelly, since Kelly was somewhat of a tyrant. O’Connor said that for the first several weeks he was terrified of making a mistake and being yelled at by Kelly.
Gene Kelly had a 103-degree fever when he danced to the title song. The director wanted to send him home, and film the scene another day, but Kelly wouldn’t hear of it. He eventually convinced the director that the massive preparations would be wasted, and to allow at least one take. That’s all it took - one take - and Kelly went home to recuperate. Most of Kelly’s performance is ad libbed - they only had time to rough out his motion up and down the street to establish camera shot opportunities; Kelly’s health was deteriorating and they had to begin filming quickly.