The original Broadway cast included Kristin Chenoweth as Glinda,  Idina Menzel as Elphaba, and Joe Grey as The Wizard. Business and popularity boomed due to very good word-of-mouth, and the box office was boosted when the show was nominated for ten Tony Awards, including Best Musical. It subsequently lost that award along with the Tony Awards for best score and best book to another new musical of the season, Avenue Q. Menzel was named Best Actress in a Musical, and the musical received two additional Tony awards—to Eugene Lee for scenic design and Susan Hilferty for costume design. The cast recording received the Grammy Award for Best Musical Show Album in 2005 and was certified platinum by the RIAA on November 30, 2006.

The story is written as a prelude to L. Frank Baum's classic book The Wonderful Wizard of Oz. It is more heavily influenced by the book than the iconic 1939 movie, The Wizard of Oz, which differs from the book in a number of ways. Set in the days prior to Dorothy's arrival from Kansas, Wicked explores the idea that the infamous antagonist we call the Wicked Witch of the West was a misconstrued, victimized person. Her alleged wickedness was merely retaliation against a charlatan wizard's corrupt government.

At Shiz University, the intelligent green-skinned teenager, Elphaba Thropp, meets beautiful and ambitious Galinda Upland (who changes her name to Glinda during the course of the musical and later becomes Glinda the Good) when the two become roommates. Their lives intertwine, and throughout the show their friendship struggles to endure extreme personality differences, opposing viewpoints, rivalry over the same love-interest, and of course Elphaba's eventual tragic fall from grace.