Charlize Therons performance inMonsterhad all the ingredients to win an Academy Award.
Second, Theron played a real-life person, and the Oscars love them a biographic performance.
Keaton was probably the only actress who could have stolen the Oscar from Theron.

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But the film may have been overly morbid and chronologically cluttered for some voters.
As for Castle-Hughes and Morton, they werent even supposed to make it into the final five.
Going against her was history: No actress under the age of 21 had ever won Best Actress.