Swan Lake is a ballet adapted on ABC's "Once Upon a Time".
- Emma Swan becomes the Black Swan after becoming a Dark One.
- Emma is referred to as the Dark Swan.
- Instead of Rothbart creating the Black Swan, she is "created" by Rumplestiltskin and Nimue, the former of whom directly tries to make her a Dark One, while the latter encourages and manipulates her evil side.
- Emma fills both the role of Odette and Odile.