Rusalka is an opera about singing. Or rather, what happens when you cannot sing. Echoing the story of The Little Mermaid, Rusalka gives up her voice to be united with a Prince. But he is distinctly put out when his bride-to-be cannot say a word. Instead he accepts the hand of a Foreign Princess and Rusalka, obeying the witch Ježibaba’s curse, is doomed to live in the depths of the lake forever.

The aria 'Song to the Moon' comes right at the beginning of the story as Rusalka, still a nymph, s...