When Kristin Chenoweth was a guest star on this episode of Glee (2009), series regular Chris Colfer told The LA Times that for him, "working with Kristin is what I can imagine what a priest would go through if they worked with Jesus.".
In the beginning of this episode, Emma talks to Will about rekindling old flames. She mentions an incident where she rekindled with her old high school flame, Andy, and three months later, Versace was dead. Emma is referring to Andrew Cunanan, the spree killer whose penultimate kill was the famed Gianni Versace. Darren Criss, who would later join the cast in Season 2 as Blaine Anderson, plays Cunanan in American Crime Story: The Assassination Of Gianni Versace. (2018)
Although only a few details of the school's production of "Cabaret" are visible in this episode, those we do see show that the "Glee" showrunners have taken some artistic license with the classic musical. Rachel is shown practicing the song "Maybe This Time," which was included in the movie, not the stage musical (although it did appear in the 1998 Donmar Warehouse stage revival, at the time this episode was filmed it did not appear in any onstage version of "Cabaret" that was legally performable by high school, college, or community theaters). Also, the dialogue that Rachel and Finn practice is a paraphrase of an exchange that occurs only in the movie, and not in any version of the musical ever staged.