Finn's opening night.

Hello everyone, I have a question someone here might have an answer to. This is a movie clip from Finn's opening night:

http://artificialnighthabits.tumblr.com/post/145867965773/who-is-the-woman-singing-and-where-can-i-find-a

(I had to cut the clip from the movie because I couldn't find a video of this specific scene anywhere!)

Who is the woman singing, what is she singing and where can I find a complete version, if it exists, of her performance?

Here’s some help, she sings these lines: “…as the evening mists were rising…”

If anyone knows, I’d thank you very much!