The Tree of Life actress told Metro that she is not like her character Celia in The Help
Asked what she is really like, Chastain said: "I'm the nerdy red-headed girl who loves Shakespeare, went to Juilliard and loved the classics.
"I don't have Celia's kind of va-va-voom. I'm not the eye candy. I'm not outgoing. I'm very shy."
Of how she has coped with Hollywood parties, she added: "Most of the time I'm the quiet girl. I like to have a conversation with people and if someone can bring me out of my shell, I really like that too.
"I'm not shy because I'm afraid of people but because I was teased when I was younger. So it always makes me kind of nervous that I'm going to get teased again. I always have that thing in me."
Chastain was earlier this month cast in upcoming Princess Diana biopic Caught in Flight.
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