It's true you can see a figure moving in the background at the end of the scene however, there are many theories to this question.
Musical theatre is a form of theatre that combines songs, spoken dialogue, acting, and dance. The story and emotional content of the piece – humor, pathos, love, anger – are communicated through the words, music, movement and technical aspects of the entertainment as an integrated whole. Although musical theatre overlaps with other theatrical forms like opera and dance, it may be distinguished by the equal importance given to the music as compared with the dialogue, movement and other elements of the works. Since the early 20th century, musical theatre stage works have generally been called, simply, musicals.
Although music has been a part of dramatic presentations since ancient times, modern Western musical theatre emerged during the 19th century, with many structural elements established by the works of Gilbert and Sullivan in Britain and those of Harrigan and Hart in America. These were followed by the numerous Edwardian musical comedies and the musical theatre works of American creators like George M. Cohan. The Princess Theatre musicals and other smart shows like Of Thee I Sing (1931) were artistic steps forward beyond revues and other frothy entertainments of the early 20th century and led to such groundbreaking works as Show Boat (1927) and Oklahoma! (1943). Some of the most famous and iconic musicals through the decades that followed include West Side Story (1957), The Fantasticks (1960), Hair (1967), A Chorus Line (1975), Les Misérables (1985), The Phantom of the Opera (1986), Rent (1994), The Producers (2001) and Wicked (2003).
Musical selections in The Wizard of Oz
The Wiz: The Super Soul Musical "Wonderful Wizard of Oz" is a musical with music and lyrics by Charlie Smalls and book by William F. Brown. It is a retelling of L. Frank Baum's The Wonderful Wizard of Oz in the context of African-American culture. It opened on October 21, 1974 at the Morris A. Mechanic Theatre in Baltimore, Maryland and moved to the Majestic Theatre with a new cast on January 5, 1975.
The 1975 Broadway production won seven Tony Awards, including Best Musical. The musical was an early example of Broadway's mainstream acceptance of works with an all-black cast. The musical has had revivals in New York, London, San Diego and the Netherlands, and a limited-run revival was presented by Encores! at New York City Center in June 2009. A film adaptation was released in 1978.
Land of Oz
The songs from the 1939 musical fantasy film The Wizard of Oz have taken their place among the most famous and instantly recognizable American songs of all time, and the film's principal song, Over the Rainbow, is perhaps the most famous song ever written for a film. Music and lyrics were by Harold Arlen and E.Y. "Yip" Harburg, who won an Academy Award for Best Song for "Over the Rainbow".
Herbert Stothart, who underscored the film, won an Academy Award for Best Original Score. Some of that underscoring was, of course, based on Harburg and Arlen's songs. Georgie Stoll was the associate conductor and screen credits were given to George Bassman, Murray Cutter (who did "Over the Rainbow"), Ken Darby and Paul Marquardt for orchestral and vocal arrangements. As usual, Roger Edens was heavily involved as the unbilled musical associate of Freed. Incidental music was contributed by Stoll, Bassman, Robert Stringer and also Conrad Salinger.]citation needed[
The Wizard of Oz
Wizard of Oz
The Land of Oz is a fantasy region containing four lands under the rule of one monarch.
It was first introduced in The Wonderful Wizard of Oz (1900) by L. Frank Baum, one of many fantasy countries that he created for his books. It achieved a greater popularity than any of his other lands attained, and after four years, he returned to it. The land was described and expanded upon in the Oz Books. An attempt to cut off the production of the series with The Emerald City of Oz (1910), by ending the story with Oz being isolated from the rest of the world, did not succeed owing to readers' reactions and Baum's financial need to write successful books.