Around Australia there are families carrying an immense burden of grief and loss. They live with the knowledge a loved one has committed a violent crime while suffering a severe mental health crisis. For decades health workers and families have worked together to remove the stigma around mental illness, highlighting how those most in danger are the patients themselves. But the confronting reality is that every year some acutely unwell people kill or commit other acts of violence after failing to get the treatment they need. On Monday Four Corners investigates how the mental health system is failing to protect the community and the patients themselves.