Black Swan is a 2010 American psychological horror film directed by Darren Aronofsky from a screenplay by Mark Heyman, John McLaughlin, and Andres Heinz, based on a story by Heinz. The film stars Natalie Portman in the lead role, with Vincent Cassel, Mila Kunis, Barbara Hershey, and Winona Ryder in supporting roles. The plot revolves around a production of Tchaikovsky's Swan Lake by the company of New York City Ballet. The production requires a ballerina to play the innocent and fragile White Swan, for which the committed dancer Nina Sayers (Portman) is a perfect fit, as well as the dark and sensual Black Swan, which are qualities better embodied by the new rival Lily (Kunis). Nina is overwhelmed by a feeling of immense pressure when she finds herself competing for the role, causing her to lose her tenuous grip on reality and descend into madness.