Carrie-Anne Moss stars in M: I 3
"This time I'm learning some things that I can't tell you what I'm learning because I'm not allowed to tell you anything," Moss says. "But I'm learning a couple things that I hadn't learned before. The first few days, you're like, 'Oh, I hate this.' I hate not being good at something. I don't do anything that I'm not good at right away."
I am assuming she is talking about keeping quiet about her character.