Williams actually plays two roles in the film not just Glinda, but also the woman Oscar loved back in Kansas, who came to him and gave him one last chance to marry her.

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He is greeted, in turn, by warring witch sisters Theodora, Evanora and Glinda, played by Mila Kunis, Rachel Weisz and Michelle Williams respectively, who show him the good and the bad in the mystical land.

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With a score by Stephen Schwartz and a book by Winnie Holzman, "Wicked" has been one of Broadway's biggest success stories since it arrived in 2003 starring Kristin Chenoweth as Glinda and Idina Menzel as Elphaba.

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The Wicked Witch, Elphaba (originally played by the excellent Idina Menzel), turns out to be good, while Glinda the Good Witch (originally played by Kristen Chenoweth) is exposed as a smug, ambitious, manipulative bitch, with little talent for sorcery.

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"Wicked, " based on Gregory Maguire's cult novel, tells the story of two young witches-to-be, one a green brooder who will be the Wicked Witch of the West and the other blond and bubbly, who will be Glinda the Good Witch.

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