1874: Only days before she is to leave the foundling home where she grew up, Agnes Resolute discovers that, as a baby, she had been abandoned with a small token of her mother: a unicorn button.

Agnes always believed her mother had been too poor to keep her, but after working as a laundress in the home she recognises the button as belonging to Genevieve Breckby, the beautiful and headstrong daughter of a local noble family. Agnes had seen Genevieve once, in the local village, and had never forgotten her.

Despite having no money, Agnes will risk everything in a quest that will take her from the bleak moors of northern England to the harsh streets of London, then on to Paris and Ceylon. As Agnes follows her mother’s trail, she makes choices that could cost her dearly. Finally, in Australia, she tracks Genevieve down. But is Genevieve capable of being the mother Agnes hopes she will be?