To add to my post above, there is also a colourized clip with a sharper image of this on youtube. I didn’t link to it because it kind of jerks in the middle, as whoever is recording it off a television slips momentarily.
I think this (link in the post above) is Lucy at her most graceful ever. Certain movements are a little off balance; you can certainly tell she is not accustomed to dancing this way daily. On the other hand, her athleticism, body control and some really lovely arm movements, taken with her acting the character flawlessly throughout the scene, impressed me very much 