It is many things! Rather, it was a new script, written just for the movie, featuring old songs written for previous mucj. Freed was a successful lyricist in the s and ’30s, collaborating with composer Nacio Herb Brown on dozens of songs for MGM musicals. Inafter essentially serving as an uncredited producer on The Wizard of OzFreed was given his own unit at MGM, where he oversaw the production of about 45 big-screen musicals some originals, some Broadway adaptations over the next 23 years, making MGM synonymous with the genre. Warner Bros. Cohan and Jerome Kern, respectively.