New York City ballet dancer Nina (Natalie Portman) enters into an intense battle of wills with a talented and ambitious new arrival (Mila Kunis) who seems intent on edging her out of the spotlight in this supernatural-flavored psychological thriller from director Darren Aronofsky. Nina covets the role of the Swan Queen in a production of Swan Lake by acclaimed theater director Thomas Leroy (Vincent Cassel). The harder Nina works to win the part, however, the more overwhelmed she becomes by her suspicions that talented newcomer Lily (Kunis) is intent on stealing it away from her. As the production draws near and Nina struggles to master the duel roles of the White Swan and the Black Swan, she grows increasingly unstable to the point where she finds it difficult to distinguish fantasy from reality. Though her burgeoning friendship with the unconventional Lily helps Nina to jettison her perfectionist instincts and find her footing as the Black Swan, the closer she gets to perfecting the role, the further her sanity erodes until she begins to experience a bizarre and profound transformation.