My favorite quote in this Paris Review piece on Sondheim is that music can make a word explode.
It sure can.
When I was fifteen years old I saw a movie called Hangover Square, another epiphany in my life. It was a moody, romantic, gothic thriller starring Laird Cregar, about a composer in London in 1900 who was ahead of his time. And whenever he heard a high note he went crazy and ran around murdering people. It had an absolutely brilliant score by Bernard Herrmann, centered around a one-movement piano concerto. I wanted to pay homage to him with this show, because I had realized that in order to scare people, which is what Sweeney Todd is about, the only way you can do it, considering that the horrors out on the street are so much greater than anything you can do on the stage, is to keep music going all the time. That’s the principle of suspense sequences in movies, and Bernard Herrmann was a master in that field. So Sweeney Todd not only has a lot of singing, it has a lot of underscoring. It’s infused with music to keep the audience in a state of tension, to make them forget they’re in a theater, and to prevent them from separating themselves from the action. I based a lot of the score on a specific chord that Herrmann uses in almost all his film work and spun it out from that. That and the “Dies Irae,” which is one of my favorite tunes and is full of menace.