The 30-year-old, who was raised in Kenya, plays a slave named Patsey in the pre-Civil War film, which is getting lots of Oscar buzz.
So how does she feel about making her debut in such a big movie?
Courtesy Darren Aronofsky
Based on the true story of Solomon Northrup, a free black man who was kidnapped and sold into slavery in Louisiana, the film also stars Chiwetel Ejiofor, Michael Fassbender and Benedict Cumberbatch.
"I'm still trying to get over the fact that my name is being mentioned with people like Brad Pitt. Honestly," Nyong'o says with a laugh. "When I was cast in his film [I thought] surely I was going to meet him one day. I wouldn't say I was star struck. I was stunned. I was like, 'Yup, this is actually happening.' "
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