] No, I don't think we can dispense with Captain Margaret in the story at all!

I agree. Margaret is not someone to be disposed of readily - she can be very handy...do you have any ideas on why they chose not to include her in the 1985 BBC version? Considering that BBC versions are practically 100% faithful to their original literary sources this seems to be a strange move. AND, they didn't miss any other minor characters ie. Lucy's sister or Sir John's children.