The action takes place in the mid-1990s in a small Australian town called Ashford. One day, a murder occurs there, which causes a wide public resonance and unsettles the islanders' society. The victim of the crime turns out to be a 17-year-old girl named Isabelle Baker. The case remains unsolved, and the killer never faces punishment. In 2020, an opened time capsule reveals a secret that helps the detective James Cormack to track down the criminal.