The actress' gran and her friends were big fans of the book and though they weren't convinced Chastain was the right choice to play Mississippi socialite Celia Foote in the film adaptation, they gave her pointers on how to play the part.
Chastain says, "My grandmother is a huge fan of the novel. When I told her I was doing the movie she and her whole book club was really excited. Then I told her I was playing Celia Foote and she was a little nervous.
"Knowing me and being such a fan of the novel, she knew I wasn't Celia at all."
The actress admits she was more nervous about her grandmother's reaction to the film than the critics'.
She adds, "I took her to the premiere with her three best friends, who were in the book club, and they loved it. She was the big critic and I passed."