What is referred to as the unsung part of a musical?

The term often referred to as the unsung part of a musical is the book. This is the foundational narrative or script of the musical that includes the dialogue and structure of the story. It is essential because it provides the context and development for the musical numbers, guiding the overall plot and character arcs. While the score (music), choreography (dance movements), and lyrics (words to the songs) are also crucial components of a musical, they typically receive more recognition and attention from audiences. The book, despite being vital for storytelling and character development, frequently operates in the background, which is why it is described as the "unsung" part of a musical.