Lupita Nyong'o "partied hard" with Michael Fassbender.
The 32-year-old actress starred as slave Patsey to Fassbender's malevolent owner Epps in '12 Years A Slave' and has revealed the pair spent "a long time hugging and dancing" to bond after playing the tough roles.
She said: "We spent a long time hugging. And we did a lot of dancing. We partied hard. It was really great. We both had a good in-and-out-of-character work sensibility.
"When we were in it, we were in it, and between takes would leave each other alone. It was like going into a boxing ring. We come, knock each other down, regroup, and at the end we hold hands."
For Lupita and her family, the scenes in the period drama hit home and she admits it was hard for her parents to watch, too.
She added to The Guardian's Weekend magazine: "My mother didn't talk about it with me for a while. And when she did, she was very mousy. She just said, 'You did really well.' But she was heartbroken. She was very quietened by it. Very moved.
"My father, he's a different kind of person. He was at the premiere in London, and he said something funny to the effect of, 'Why did you let them beat you like that?'"