The iconic actress has been referenced by the show's characters on a number of occasions, usually by aspiring Broadway performers Rachel Berry and Kurt Hummel, who are portrayed by Lea Michele and Chris Colfer respectively.
EW has confirmed that LuPone will share her scenes with both Michele and her character's on-off love interest Finn Hudson, played by Cory Monteith.
"On set right now working with one of my all-time idols," Michele tweeted earlier this week. "Another day where Glee makes one of my dreams come true."
LuPone recently starred in the original Broadway production Women on the Verge of a Nervous Breakdown, but is best known for her leading roles in both the 1979 musical Evita and the original London production of Les Misérables.
Glee is scheduled to air its second season finale on May 24.
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