chunk: Nina trashes the apartment and slams her bedroom door on her mother's hands, and has hallucinations of becoming freakishly swanlike. Concerned about Nina's behavior, her mother tries to prevent her from performing on opening night in an effort to keep her daughter safe. An enraged Nina forces her way out of the apartment. Thomas had assigned understudy Lily to take over, but is impressed at Nina's confidence, and lets her play the Swan Queen. The first act goes well, until Nina is distracted by a hallucination during a lift, causing her partner to drop her. Distraught, she returns to her dressing room and finds Lily there. Lily announces her plans to play the Black Swan. Nina shoves her into a mirror, shattering it. Lily, seemingly dead, awakens, and her face changes shape, now a copy of Nina's. The doppelganger starts to strangle Nina, who then grabs a shard of glass and stabs her rival in the abdomen, apparently killing her. The doppelganger's face reverts to that of Lily's. Nina