Mila Kunis will be Natalie Portman's nemesis. The actress is in discussions to star opposite Portman in Darren Aronofsky's supernatural drama "
Black Swan." The pic centers on a talented ballerina (Portman) in the New York City Ballet who is tormented by a rival who might or might not be a figment of the dancer's imagination.
Kunis will play the rival, Lilly, with strange occurrences between the two increasing as they prepare for a big performance.