Eastern Sydney in the 1920s. Slumland streets controlled by two women - crime bosses Kate Leigh and Tilly Devine. Lyndsey Collier, an ambitious country girl, joins the Women's Police. As her work draws her into Sydney's underworld, Lyndsey discovers a greater threat than the criminals she is investigating. Betrayed by a corrupt police officer, Lyndsey escapes into the shadows of underworld Sydney to protect the man she loves. A lifetime away and nearing death, Lyndsey begins to tell her story to Abigail Hollingsworth, a nurse at Kirkland Home for the Elderly. As she is caught up in the tale, Abby must also confront her own troubled marriage. A gritty, haunting story of loss and regret, and of a love that brings together two women generations apart.