I don't get why certain people think Cersei was behaving out of character in this ep. Sure, she is less dumb and bitchy in the show, but it's important to note that she only has three scenes in this episode, and each one of them is with someone who has the power to convict Tyrion (Margaery by extension of her father, obvs). She is playing at being calm, although I do believe her mourning is very real. But in certain moments, and I have to habd it to Lena Headey for this, you can see how angry she really is.
