No, Maggie's really not needed in the movie. If they want to tell the story in two hours or so, they can quite easily leave out Maggie and do an HoDS-esque retelling of the initial Barnabas storyline. Aside from that, Kathryn Leigh Scott looked really good in that role, but I don't find Keira Knightley the slightest bit attractive, probably because of the bad nose job. Just my opinion. If they are going to do Maggie in the movie, Emmy Rossum is still my ideal.