 Schwartz uses the " Unlimited " theme as the second major motif running through the score . Although not included as a titled song , the theme appears as an interlude in several of the musical numbers . In a tribute to Harold Arlen , who wrote the score for the 1939 film adaptation , the " Unlimited " melody incorporates the first seven notes of the song " Over the Rainbow . " Schwartz included it as an inside joke as , " according to copyright law , when you get to the eighth note , then people can come and say , ' Oh you stole our tune . ' And of course obviously it 's also disguised in that it 's completely different rhythmically . And it 's also harmonized completely differently .... It 's over a different chord and so on , but still it 's the first seven notes of ' Somewhere Over the Rainbow ' " . Schwartz further obscured the motif 's origin by setting it in a minor key in most instances . This also creates contrast in the songs in which it forms a part , for example in " Defying Gravity " , which is written primarily in the key of D @-@ flat major . In the song " The Wicked Witch of the East " , however , when Elphaba finally uses her powers to let her sister walk , the " Unlimited " theme is played in a major key . 
