Catherine Corless has made headlines around the world for exposing the horrifying story of a mass grave of almost 800 infants at a former institution for unmarried mothers run by nuns. Corless has been described as "Ireland's Erin Brockovich"; an ordinary woman and amateur historian who, in her dogged pursuit of the truth, took on the Catholic Church, the Irish government and members of her own community - and won. The case has shaken Ireland and provoked very difficult questions about how women and children were treated at Catholic institutions in the past.

Presenter: Becky Milligan Producer: Ben Crighton.