During the Techicolor sequence, virtually everything aside from the blue gown is black or white. The wall decoration is a black and white mural and all of the other women wear grey, black, or white. This makes the blue gown jump out of the scene.
Stuart Robertson, who played 'Freddie, the Bandleader', was the brother of Anna Neagle.
The "Alice Blue Gown" is a specific shade of blue named after Alice Roosevelt Longworth, the daughter of President Teddy Roosevelt. "Alice blue" became a fashion sensation and the chic color of the era.
This was previously produced as a silent film, Irene (1926) with Colleen Moore in the title role.
About twenty-five minutes of this film are in color, from the moment that Irene (Anna Neagle) enters the ballroom dressed in her blue gown, up through the moment when she returns home and sings the song "Alice Blue Gown".
This was adapted from a popular Broadway musical that originally opened at the Vanderbilt Theater on Nov. 18, 1919 and ran for 675 performances. Irene Dunne and Jeanette MacDonald were replacement cast members during its long run. The musical was later revived with Debbie Reynolds in the lead. This version opened at the Minskoff Theater in New York on March 13, 1973 and ran for 594 performances.
The Radio City Rockettes wound up with most of their scenes on the cutting room floor following previews, save for a brief montage sequence in the "Alice Blue Gown" number.
Lux Radio Theatre version starring Jeanette MacDonald and Regis Toomey aired June, 1936.