In August, 2020, 21 year old Katie Simpson was rushed to hospital in Derry with severe injuries. The explanation given at the time was that she had tried to take her own life, but almost immediately, there were questions.
Quiet ones at first from those who knew her, from people who felt that something about the story didn't sit right.
What followed was a case that would unravel layer by layer, exposing inconsistencies, missed opportunities, and one that would become the focus of a murder investigation and ultimately a damning review of the PSNI's handling of the case.
Ciara is joined by Allison Morris from the Belfast Telegraph and Katie's aunt Paula Mullan