Question: What film starring Natalie Portman appeared at the 67th Venice International Film Festival?
Related documents: [0]  [DOC] The 67th annual Venice International Film Festival held in Venice, Italy, took place from 1 to 11 September 2010. American film director and screenwriter Quentin Tarantino was head of the Jury. John Woo was awarded the Golden Lion for Lifetime Achievement prior to the start of the Festival. The opening film was Darren Aronofsky's "Black Swan". [END] 
[1]  [DOC] Black Swan is a 2010 American psychological horror film directed by Darren Aronofsky. The screenplay by Mark Heyman, Andres Heinz and John McLaughlin is from a story by Heinz. It stars Natalie Portman, Vincent Cassel, Mila Kunis, Barbara Hershey and Winona Ryder. The plot revolves around a production of Tchaikovsky's "Swan Lake" ballet by a prestigious New York City company. The production requires a ballerina to play the innocent and fragile White Swan, for which the committed dancer Nina (Portman) is a perfect fit, as well as the dark and sensual Black Swan, which are qualities better embodied by the new arrival Lily (Kunis). Nina is overwhelmed by a feeling of immense pressure when she finds herself competing for the part, causing her to lose her tenuous grip on reality and descend into a living nightmare. [END] 
Answer: 
Black Swan
Black Swan