A mute Scots people named Ada McGrath is sold by her father into marriage to a New Zealand frontiersman named Alisdair Stewart, bringing her young daughter Flora with her. Ada has not spoken a word since she was six and no one, including herself, knows why. She expresses herself through her piano playing and through sign language, for which her daughter has served as the interpreter. Flora, it is later learned, is the product of a relationship with a teacher with whom Ada believed she could communicate through her mind, but who "became frightened and stopped listening", and thus left her.