Lydia Harvey was meant to disappear. She was young and working class; she'd walked the streets, worked in brothels, and had no money of her own. In 1910, politicians, pimps, policemen and moral reformers saw her as just one of many 'girls who disappeared'. But when she took the stand to give testimony at the trial of her traffickers, she ensured she'd never be forgotten. Historian Julia Laite traces Lydia's extraordinary life from her home in New Zealand to the streets of Buenos Aires and safe houses of London. She also reveals the lives of international traffickers Antonio Carvelli and his mysterious wife Marie, the policemen who tracked them down, the journalists who stoked the scandal, and Eilidh MacDougall, who made it her life's mission to help women who'd been abused and disbelieved. Together, they tell an immersive story of crime, travel and sexual exploitation, of lives long overlooked and forgotten by history, and of a world transforming into the 20th century.