Some of the most memorable songs from Joe Iconis' breakout show Be More Chill take place at a Halloween party, a location that serves as a metaphor for the theme of performing a new identity for social acceptance. And since performances began February 13 at the Lyceum Theatre (with an official opening scheduled for March 10) that scene earns its place in the Broadway canon

Iconis recently told Playbill that “when we wrote the show [which premiered in 2015], there weren’t actually any other musicals with Halloween Party blowout sequences, so just by existing, we were automatically the greatest. Now we’ve got some competition.” That competition came in the form of Mean Girls, which opened on Broadway on April 8, 2018.

While it's true that the Halloween parties in Mean Girls and Be More Chill are especially similar in the function they serve in the musical, Halloween parties—or at least costume parties—have actually been a part of musical theatre since the earliest days, though they became scarce in recent years.

Here, with the resources of the New York Public Library of the Performing Arts, Playbill looks at seven times costume balls and Halloween parties grabbed the spotlight:

The Black Crook, 1866

The 1866 proto-musical, The Black Crook featured a masquerade ball in the third act in which the protagonist, Rodolphe, rescues his girlfriend, Amina, from the clutches of the evil Count Wolfenstein. When the Count hears a rumor that Rodolphe is at the party, he orders everyone to “unmask.” Rodolphe is discovered, but successfully fights off the Count’s guards with the help of an army led by the Fairy Queen, Stalacta. The programs from the original production suggest the producers saw an opportunity in this scene to feature both the balletic talents of their performers and a display of female sexuality and inserted a “Dance de Amazons” for the fairy army. The religious establishment of the time decried the scene as being too sexy (or, in the parlance of the 19th century, “an indecent and demoralizing exhibition”).

So even the costume parties staged more than 100 years ago provide, in the words of Iconis, “a rad excuse,” for costumes with sex appeal (Mean Girls: “I give you sexy corn”) and the theatricality of performing an identity other than one’s own.

Die Fledermaus, 1874

Like The Black Crook, Strauss’ 1874 operetta Die Fledermaus is, in many ways, a proto-musical. Although now usually performed in opera houses, the piece has, over the last century, fit comfortably into the seasons of musical theatre companies such as the St. Louis Muny and the New York City Center Light Opera (where, in 1954, it was preceded by Show Boat and followed by Carousel). In 1950, the Metropolitan Opera commissioned and presented an English translation of the German lyrics by musical theatre lyricist Howard Dietz.

The operetta takes its title from the nickname of Dr. Falke, who once, dressed as a bat (or in German, Fledermaus), got drunk at a costume party and was left by his friend, Eisenstein, in the town square. He awoke in the morning to find he had been christened Dr. Fledermaus.

In the second act of the musical, Falke is on his way to another ball where he plans to exact his revenge on Eisenstein. Eisenstein’s wife, Rosalinde, believes her husband is on his way to jail for a minor offense. Eisenstein, instead, is skipping his appointment with the jailer in order to attend the ball as well (dressed as a French Marquis). Falke has secretly invited the jailer (dressed as a French aristocrat as well), Eisenstein’s wife (dressed as a Hungarian aristocrat), and Eisenstein’s maid (pretending to be an actress) to the party. Eisenstein flirts first with the maid, and then (unknowingly) with his own wife, attempting to convince her to “unmask.” The eroticism of masking and unmasking is barely even subtextual in this scene.

My Fair Lady, 1956

Although the guests of the Embassy ball in My Fair Lady are not masked, it is clear many of the guests assume identities other than their own through affected speech. Higgins’ former student, the linguist Zoltan Karpathy, tells Higgins he makes it his business to “unmask” and blackmail those attempting to assume false identities. Eliza, however, in what is perhaps a nod to Rosalinde’s costume in Die Fledermaus, manages to convince him that she is Hungarian royalty (the scene does not appear in Pygmalion, the play on which the musical in based).

Again, the “costume” has a kind of erotic appeal. Although worn imperfectly in the earlier scene at the Ascot races, Eliza’s manages to charm Freddy Eynsford-Hill into waiting outside her door “on the street where she lives.” Higgins, in his own way, comes to fall for the unmasked woman, and, after the ball, confesses he has “grown accustomed to her face.”

Sweeney Todd, 1979

A much darker version of the eroticism of masked parties plays out in the flashback in Sweeney Todd. Joanna is invited by Judge Turpin to his house where she finds she has unknowingly entered a masked ball. The Judge rapes Joanna while the masked guests watch as voyeurs. Here, the masked party-goers are both a metaphor for a society that complacently watches atrocities without making any attempt to intervene. It is a favorite meta-theatrical metaphor of the original director Harold Prince: the party-goers are like those in the audience at a play who watch passively in the anonymity of a crowd while terrible things happen. The anonymity of being in crowd of strangers allows individuals to become like the masked party goers who do nothing to help those in dire need and suffer no obvious societal repercussions for their inaction.

The Phantom of the Opera, 1988

Another Hal Prince show, The Phantom of the Opera, begins its second act with a masquerade. The young lovers discover themselves, unmask, and declare their passion (“A secret engagement--look your future bride!”). Their passion is interrupted by the appearance of the Red Death, the Phantom of the Opera. Although the Phantom usually appears only in the shadows or mirrors, at a party where wearing masks is expected he is able to join society. If post-industrial urban society is composed of those who can chose to be anonymous, a man who always wears a mask can only truly join society at a masked ball. However, the Phantom, unaccustomed to blending in, wears an ostentatious costume and quickly becomes the center of attention. The scene is the moment the Phantom throws down the gauntlet to Christine, but also reveals the deeper love that has developed between her and Raoul.

Mean Girls, 2018

Mean Girls has a famous Halloween scene adapted closely from its source movie. The ability to assume different identities is celebrated by the characters who sing that on Halloween they can be “who I wanna be and sexy.” Karen’s observation that “When you are the hot one / It’s a full time gig / Looking like what people wanna see” acknowledges how much work goes into the performance of her identity. Again, one of the characters, the protagonist, Cady, unwittingly arrives in a costume that prevents her from fitting in: a “scary” zombie bride costume rather than something "sexy." The costume choice actually impresses Aaron, Cady's crush, but prevents her from fitting in with the popular mean girls who feel, in the words of one of them, that “If you don’t dress slutty, that’s slut-shaming us.” This also marks the scene in which Regina reclaims Aaron, fueling Cady’s revenge plot with Janis and Damian that sets the full plot in motion.

Be More Chill, 2019

The costumes in the party appear to be adolescent attempts to get attention (“I stole my older brother’s Jason mask / and I don’t have a machete but a loaf of bread will do”). As is common in Halloween party scenes in movies and theatre, many of the girls’ costumes are sexualized (Brooke sings “You can kinda see my business / But I’ll act like I don’t know”). The character who is most excluded from the group, Michael (who spends most of the party hiding “in the bathroom”), is also the only person not wearing anything that could be called a costume. He wasn’t invited, but sneaks in under cover of what he calls “this clever disguise” —a sweater with the word “Creeps” on it. He is the only one who is not attempting to perform a different identity at the party, and as a result he is excluded from the group. The party marks a moment of realization for both Michael and protagonist Jeremy.

Early in the show, Christine in Be More Chill confesses she “loves play rehearsal” because “It's just so universal / Getting to try playing so many parts.” This excitement is widely shared amongst those who love to make and watch theatre, and a costume party is one of the very few places outside of “play rehearsal” where this happens. It’s not surprising, then, that masquerades are such a popular trope in musical theatre.

Doug Reside is the Lewis and Dorothy Cullman Curator for the Billy Rose Theatre Division for The New York Public Library for the Performing Arts.