Haven't read the book and must say I found the TV ending disappointing. Was the twist at the end meant to be that she really had asked him to kill Mark so she was really guilty? I didn't understand why she went to see him at the end - I thought she would have thought she'd had a lucky escape at the end of the court case especially when she discovered he was just a fantasist who would try it on with anyone. Maybe it was a problem of casting - I couldn't see what anyone would see in Ben Chaplin that would make them lose their inhibitions in that way. And while she might have been turned on thinking he was MI5 (if that's what does it for you) once she realised he was just a security advisor surely even that thrill would have gone?
I think she had to keep her own fantasy alive, otherwise she would have been someone who turned her life upside down and almost destroyed her family for an unstable underachiever with a violent streak. So instead she kept up the fantasy that he was her knight in shining armour - you could see her relief after Gary told her the real(?) version of the monkey experiment, that it confirmed for her that Mark would never betray her. It was only at the very end, when Mark reminded her about what she'd said in the flat and she realised that he had taken her seriously, that she could really see how much of a nutter he was.
Can someone also please clarify - I thought the woman shouting from the public gallery was Mark's wife. Is that right?
Yes.