In the 2010 movie Black Swan, Nina and Lily are the two main characters, but a couple of times in the movie, a third girl pops up out of nowhere. I cannot find any information about who this third girl is or even anyone asking who she is (or even who played her).
She pops first when Nina is “exploring herself” in the bathtub (figure 1), and again during the sex scene (figure 2). I thought that maybe she has something to do with sex, but she did not show up in the scene when Nina woke up and… failed to notice her mother sitting next to the bed.
The closest I can come to finding an explanation is a theory about Nina possibly spawning a new personality, which might make sense since the girl looks a little like her, but it seems that people that propose that theory are actually talking about Lily being the new personality, not this third girl. One person seemed to be wondering the same thing, but the answer they got again referred to Lily, not the mysterious, unnamed girl.
I had wondered if maybe she is a morph between Nina and Lily, but doesn’t really seem to be. Whether she was CG or an actual actress, the filmmakers specifically and purposely made a point of putting her in and even highlighting her appearances, so she must be relevant.
Does anyone have any ideas why they put this other girl in the movie and who/what she is supposed to represent?
Figure 1: The mysterious girl shows up during the bathtub scene and looks similar to Nina
Figure 2: The mysterious girl shows up again during the sex-scene and looks different