Dr Nikki Alexander, Dr Thomas Chamberlain and Dr Jack Hodgson form a dedicated team of forensic pathologists who try to work out how and why the victim died. This series sees Nikki investigate a murder that's a carbon copy of a case from her past. She soon suspects that the killings are personal to her. But who will believe her? Jack creates tension when he finds himself aligned with a police complaints investigator over the accidental shooting of a girl by armed police.

A seemingly random killing in the remote countryside leads Nikki and Jack into the dangerous underbelly of a criminal world; whilst an ex-convict is killed and suspicion lands on a recently released murderer. As other former long term prisoners out on a life licence come under scrutiny, the team learn how fragile their freedom is.