All Waiting Is Long tells the stories of the Morgan sisters, a study in contrasts. In 1930, twenty-five-year-old Violet travels with her sixteen-year-old sister Lily from Scranton, Pennsylvania, to the Good Shepherd Infant Asylum in Philadelphia, so Lily can deliver her illegitimate child in secret. In doing so, Violet jeopardizes her engagement to her longtime sweetheart, Stanley Adamski. Meanwhile, Mother Mary Joseph, who runs the Good Shepherd, has no idea the asylum's physician, Dr. Peters, is involved in eugenics and experimenting on the girls with various sterilization techniques.

Five years later, Lily and Violet are back home in Scranton, one married, one about to be, each finding her own way in a place where a woman's worth is tied to her virtue. Against the backdrop of the sweeping eugenics movement and rogue coal mine strikes, the Morgan sisters must choose between duty and desire. Either way, they risk losing their marriages and each other.