At the start of a new series by Guardian Australia, David Marr investigates the background to Australia’s unprecedented royal commission on institutional responses to child sexual abuse – investigating a centuries-long story of faith, money, power and abuse. Marr traces the story through the US, Ireland and, eventually, to Australia. He hears from victims, experts and participants in the commission as he investigates: why has the truth taken so long to emerge? Warning: some of the material in this podcast is explicit and upsetting • Why Australia’s royal commission on child sexual abuse had to happen – explainer