Watch a trailer for the reunion episode below:
Concert performers include Lora Lee Gayer, Sas Goldberg, Curt Hansen, Curtis Holbrook, Andrew Keenan-Bolger, Derek Klena, Jay Armstrong Johnson, Carrie Manolakos, Lindsay Mendez, Ana Nogueira, Brynn O'Malley, Christina Sajous, Vanessa Ray, Dani Spieler, Dana Steingold, Nina Sturtz Labarre, Alysha Umphress, Natalie Weiss, Cody Williams, Jake Wilson and Cortney Wolfson.
For more information or to purchase tickets to the Joe's Pub concert, click here.
Special guests in original episodes of the series included Tituss Burgess, Jesse Tyler Ferguson, Sutton Foster, John Gallagher Jr., Elizabeth Gillies, Whoopi Goldberg, Ariana Grande, Jonathan Groff, Cheyenne Jackson and Allison Janney.
Special guests set to appear in the reunion episode include Jake Wilson, Sas Goldberg, Cole Escola, Andrew Keenan-Bolger, LaChanze, Ana Nogueira, Vanessa Ray, Dani Spieler, Nina Sturtz Labarre, Alysha Umphress and Cortney Wolfson.