Hortense Cumberbatch, a successful Black British middle class Optometry in London who was adopted as a child, has chosen to trace her family history after the death of her adoptive mother. After being warned by public officials about the troubles she could face by tracking her birth mother down, she continues her investigation and is baffled to learn that her birth mother is white but does not resent this fact and wants to know more about her mother's past. Her birth mother, Cynthia Purley, is working class and downwardly mobile. Hortense meets her and later meets Cynthia's brother, Maurice Purley, a photographer, his wife Monica, and Cynthia's daughter Roxanne, a street cleaner.