Idina Menzel and Kristin Chenoweth Sing Wicked Songs in Concert Preview

Previews of performances from NBC's A Very Wicked Halloween: Celebrating 15 Years on Broadway have been released.

Watch a clip of Idina Menzel singing "Defying Gravity":

See Kristin Chenoweth perform "Popular":

A Very Wicked Halloween, airing October 29 on NBC at 10pm, will reunite Tony Award winners Menzel and Chenoweth, the original Elphaba and Glinda, who will perform and serve as hosts for the special. Additional guest performers include Ariana Grande, Adam Lambert, Ledisi, Pentatonix, and the current Broadway company of Wicked.

Based on the novel of the same name by Gregory Maguire, Wicked is set in the land of Oz and tells the story of young women Glinda and Elphaba, who grow up to become Glinda the Good Witch and the Wicked Witch of the West, respectively. Featuring music and lyrics by Stephen Schwartz and a book by Winnie Holzman, the production is directed by Joe Mantello, with musical staging by Wayne Cilento.