How to Write a Musical: The Purpose of the Music

Book of Mormon, How to write a musical

Book of Mormon, How to write a musical

This is part 2 of a series on how to write a musical. Start from the beginning with a brief history of musicals or jump forward to learn how to select song posts!

This is part 2 of our series on how to write a musical, inspired by a friend’s efforts to write a musical about an undercooked piece of pasta named Al Dente. Today, we’re going to take a quick look at the role of music in musical theater and what a composer might want to know before diving in.

It might seem as easy as just writing a script and then putting it to music, but if you want to make a musical that works, there are a few things you should probably know beforehand. Also, understanding the role of the music can give us constraints that will make our songwriting a little easier.

Quick disclaimer: I’m not a Broadway expert, but rather a curious musician sharing some of the insights I’ve found. If you’re looking for more detail, John Kenrick’s is extremely useful. And feel free to comment below if you have more to add!

The Overarching Rule: Music Serves the Story

In talking to Broadway experts and reading about musicals, there’s one fact that comes up over and over again: the story comes first, and the music exists to help bring that story to life. As important as the music is, it’s really there to serve the story, to make you feel what the characters feel, to communicate the plot in an entertaining way, or to illuminate moments of great tension and drama.

This is one way that musicals contrast with say, operas. While operas are often built upon classic story lines, the music usually comes first, and you don’t even really need to follow the story to appreciate it. That’s definitely not the case on Broadway, where the music rarely lets you forget where you are in the story.

Famed composer Stephen Schwartz says that musicals are all about the structure. As Schwartz says, the structure is like the frame of a house. Once you have a solid frame, you can swap out various furnishings, windows, paint color, etc. as much as you want to give it color and personality. The structure in this case is the story, and the details are the songs.

So given all that, what is the purpose of music in musicals?

1. To bring the characters to life

A primary purpose of the music is to allow the central characters to express themselves and their motivations. One of the most common types of song you find early in a musical is an “I want” song — a song that sets up the inner conflict of the main character by illuminating that character’s desires and longings, like “Wouldn’t It Be Loverly?” in My Fair Lady, or “The Wizard and I” in Wicked, or even “Somewhere over the Rainbow”. This concept reminds me of step one in Joseph Campbell’s theory of the hero’s journey: a slightly troubled character gets called to adventure and that drives the rest of the action of the plot. Music allows the character to express that inner turmoil, which will end up driving the central conflict of the show.

Beyond “I want” songs, any character can have a song that explains a little more about who they are and their motivations. “Jet Song” from West Side Story establishes and introduces all the characters from the Jets gang, while “America” illuminates the desires and tensions of the Sharks and the Puerto Rican community. These “I am”-style songs are great because musically, whatever themes you use here can then be teased again any time you want to remind the audience of those characters’ motivations or context. They can be great through-lines. “Cell Block Tango” from Chicago is another great example.

2. To move the action forward

John Kenrick talks about three types of songs that move the action or characters forward in a key way: transition, realization, and decision. These songs are exactly what they sound like: a transition song reflects a moment of change (“The Rain in Spain” from My Fair Lady). A realization song is when a character is struck by a moment of understanding (“Defying Gravity” from Wicked). And a decision song captures a moment of great resolve in a character who’s been struggling with a decision (“I Believe” from The Book of Mormon). These songs can be a great way to move the story forward and help the audience understand exactly what’s happening with a musical flourish.

3. To express moments of high emotion and drama

There’s a proverb that says, “when the emotion becomes too strong for speech you sing; when it becomes too strong for song, you dance.”

Even in the world of musicals, it wouldn’t make a ton of sense for people just randomly to break into song — they need to be sparked by emotion. After her first successful day with Professor Higgins, Eliza Doolittle is so excited that she literally bursts into song (“I Could Have Danced All Night” from My Fair Lady). As every movie-lover knows, the music in these instances helps the audience connect with the feeling of a scene more deeply, narrating the emotions through harmony, rhythm, melody, vibe, and overall tone.

(For a better understanding of why, read our article about why music drives emotions.)

Probably the best example of how music expresses moments of high emotion is through love songs (“Tonight” from West Side Story or “Johanna” from Sweeney Todd). That said, it’s also a great way to express the tension and drama of the show’s most climactic moments (“One Day More” from Les Misérables).

4. To provide comic relief or just break things up

At the end of the day, music can also just be a great way to break up the story and keep the audience interested. Songs like “Gee, Officer Krupke” from West Side Story don’t seem to serve the story too much, but when you realize the audience has recently been sitting through the murder of teenagers, you can understand why the creators felt like they needed to add a lighter song to the mix. “Season of Love” from Rent perhaps performs a similar function. Or “Master of the House” from Les Misérables. In these cases, the music adds a little break in the action and a chance for the audience to tap their feet without having to pay quite as much attention.

5. To sell more tickets

Back in the early 20th Century when the music of musical theater was often the same as the popular music of the day, composers and producers would try to have a hit song in their musicals, even if it didn’t necessarily serve the story. Not surprisingly, one hit song could guarantee more ticket sales and attention. Examples include Irving Berlin’s “Blue Skies” originally from the now-forgotten musical Betsy (which was then moved to the more successful musical White Christmas) or Gershwin’s “I Got Rhythm” from Girl Crazy.

While you don’t often hear songs from musicals topping the pop charts as much today, “Let It Go” from Frozen proves that still spending the time to write a hit song can drive a lot of success for your musical (that song is also a good example of a “realization” song). “Falling Slowly” from Once is another song that drove more attention to the musical.

All in all, Schwartz suggests that the key to good songs in a musical is your ability to get inside the characters’ heads as much as possible and figure out what they would likely sing about. Given their motivations, what would cause the character so much emotion that they would be compelled to break into song?

Do you have any other great examples of ways songs are used in musicals that could get someone started, share them in the comments below!

This is part 1 of a series on how to write a musical. Click here to see what you’ve missed, and here for the next article.

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