When an officer of the missing persons unit is brought in, the team are looking for a serial killer who has killed 12 victims in the past 10 years.

The Homicide team look into the hit-and-run death of Yvette Simpson after a person comes forward some weeks later and says that she was intentionally hit by the car. The case leads them to the police union and a subsequent investigation by the public standards committee which brings Bernice back in contact with Michael Mellor who brought corruption charges before her previously. Can they work together to find Yvette's killer?