She is very good
I don't know anything about her, but I have been watching the series of Firefly recently, and she stands out to me as being perhaps the best.
Is she one of those method actors or something? I really love the show, and I love the cast too. But she stands out even amongst those others. At first I thought she was maybe too pretty for the role, but now I just find her totally believable. My favourite thing is that she does these facial expressions that say a thousand words. It's really cool.
It looks like she has done lots of other shows and films, so I'll look forward to seeing her again in something else.