So who was the heroine?
At first it seemed to be Sarah, who was just trying to rule the kingdom and fight off the competition.
But...
[spoiler] I think Sarah was actually the villainess of the piece. She bullied the queen into imbecility and left her nothing to do with her time but be miserable, and she was a crap warmongering tax-happy ruler. But of course Abigail was a little monster and couldn't be the heroine... I think at the end of the piece Queen Anne herself was the heroine, she'd gotten rid of her horrible bully of a friend, gotten the whip hand on her dreadful replacement, and was finally ruling in her own right. I don't know if that makes for a satisfying film, although maybe it will be when I watch it again. [/spoiler]