“Quite often we have characters that are very black or white. They’re good or they’re bad, and these ones aren’t. They’ve got layers to them. I think that she is a good person, but she’s just behaving badly. She’s got very obvious flaws in her personality that are not particularly nice traits, but that still doesn’t mean that she’s a bad person. I think it’s always interesting to look at the flaws because that’s what makes characters, and people, interesting. You want to have negative aspects, so that you can look at the positive as well. I think that she’s a fascinating character.” Keira Knightley on playing Cecilia Tallis.