The musical drama, musical play, or simply the musical is an evening-length theater piece integrating spoken dialogue and sung music in order to tell a story. The story, or book, while it may take up serious matters, always has a significant, if not dominant, comic element, and the characters in the story are recognizable and accessible to all members of the audience. The music, usually a set of songs, is composed in a popular idiom.
The foremost criterion for evaluating a musical’s artistic success is the integration of book and music. In the best musicals, songs are like compressed scenes of dialogue, revealing character and moving the plot along. A song should never impede the action of the story. Also, in the very best musicals there is a unity of style or tone to the songs; they constitute a musical suite.
Secondary criteria for judging musicals are often derived from the relation of the story and musical idiom to the audience. A story can stray too far from an audience’s experience or expectations, either in the general nature of the narrative events or in the relative degree of comedy in the plot. Music similarly challenges an audience when it approaches the technical or conceptual complexity of classical forms. Such musicals, even if they come from Broadway or London’s West End, are frequently denied the label “musical,” sometimes by their composers. Instead, they are called operettas or even operas.
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