Catherine Corless, a local historian from County Galway in the Republic of Ireland, discovered that hundreds of babies and young children had died in a home for unmarried pregnant women. It was run by Roman Catholic nuns in her hometown of Tuam, and these children had died of neglect and malnutrition, their deaths unrecorded, their bodies buried in unmarked graves. This documentary investigates the allegations levelled against both the Irish state and its religious order: that they were jointly responsible for a decades-long campaign of institutional neglect which ultimately led to the deaths of thousands of children.