Events leading up to the 1996 Port Arthur massacre on Tasmania in an attempt to understand why and how the atrocity occurred.

Roy Freeman, an ex-homicide detective with a fractured memory, is forced to revisit a case he can't remember. As a man's life hangs in the balance on death row, Freeman must piece together the brutal evidence from a decade-old murder investigation, uncovering a sinister web of buried secrets and betrayals linking to his past. With only instincts to trust, he faces a chilling truth - sometimes, it's best to let sleeping dogs lie.