Anyone who knows anything about Wicked is likely aware of how big a role the awe-inspiring voices of, and natural chemistry between, original Broadway stars Idina Menzel and Kristin Chenoweth played in turning the musical into an instant mega-hit.

“There was no world where we wouldn’t invite them to come be a part of this,” director Jon M. Chu tells The Hollywood Reporter. “The question for us was, how, and how much are they willing to do in it, and how much can the story itself handle it? Because they’re such iconic people and especially to these roles.”