Mara and Frankie are cousins and best friends, growing up in the stifling atmosphere of Swansea in the 1950s, amid a bickering yet close-knit extended family. But their passionate friendship comes under threat as they reach adolescence in the heady atmosphere of the Sixties—a decade in which the conventions of family and kinship are overturned. Years later, as Mara begins to confront the questions surrounding Frankie's death, she is drawn back into their secret past and the struggles of a generation betrayed by its own values.