The Hollywood musical was long a staple of the film industry, at least from the beginning of the sound era to the early 1970s, and the form continues to reappear from time to time. It has fallen into disfavor in recent years because it is viewed as artificial and unrealistic, given that orchestras play where there are no orchestras and people break into song in lieu of dialogue when the mood strikes them. Filmmakers always accepted the conventions and made use of them, but with Bob Fosse's film version of Cabaret (Bob Fosse, 1972), the trend in filmmaking turned away from the conventions of the musical in the belief that audiences would no longer accept them. Cabaret presented all of its musical numbers in a naturalistic way so that they took place as they would in life--on stage, for instance, or as part of a public rally. People no longer broke into song simply to express their inner feelings or to advance the plot, and many filmmakers shied away from the musical altogether because it was viewed as an artificial form in an increasingly naturalistic cinema. The American film Singin' in the Rain (Gene Kelly, Stanley Donen, 1952) is a good example of how the conventions were treated through most of the history of the musical, while the British miniseries The Singing Detective (Jon Amiel, 1986) makes a different use of some of the conventions while standing as a very different sort of film.
Hodsdon (1996) points out that the conventions of the Hollywood musical were formed in the Fred Astaire Ginger Rogers musicals made at RKO in the 1930s and further developed by Metro-Goldwyn-Mayer in the 1940s and early 1950s. Hodsdon cites a definition offered by Thomas Schatz:
Rather than create a realistic or at least plausible world whose inhabitants find reasonable motives for breaking into song (rehearsals, shows, etc.), the music itself seems to determine the attitudes, values and demeanor of the principal characters. As the m...