When 51-year-old Catherine Corless decided to enrol in an evening course in local history, she had no idea where the decision would lead her. Catherine began researching the Tuam Mother and Baby Home in County Galway, which she had passed every day as a child on her way to school. Slowly, she began to uncover a dark secret that had been kept for many years: the bodies of 796 babies had been buried in what she believed to be a sewage tank on the grounds. But who were these children, how did they get there and who had been responsible for looking after them? Determined to ask why, Catherine doggedly set about investigating further. Her quest for justice for the Tuam babies and those who went through that home would span over a decade as, often against fierce resistance, she brought to light a terrible truth that shocked the world, impacted the Vatican, and led to a Commission of Investigation in Ireland.