Series 5, Episode 6

Series 5, Episode 5

Series 5, Episode 4

Series 5, Episode 2

Perez and his team re-open a 23-year-old cold case of teenager Lizzie Kilmuir, found strangled to death on a kiln, when journalist Sally McColl is found murdered in the same way. Sally's father was a former officer who lead the investigation of the murdered teen, and suspicion lies on Thomas Malone, a released convicted murderer, and estranged friend of Lizzie's sister.

Troubled about what he's discovered about a scarf left at the crime scene, Perez has to face the fact that Duncan may have been involved in Lizzie's murder and, potentially, Sally's, as well. A DNA test reveals a secret about Duncan's real son.

The attack upon Jo has affected the team considerably. Sandy, particularly, is struggling with feelings of guilt. Perez struggles to keep everyone on track, especially since the pressure to re-arrest Malone has never been stronger.

Ignoring Secret Service warnings, Perez and Tosh track down Mathias Soderland. Back on Shetland, a beach memorial service is held for Sally McColl.

With Andreas Hagan their strongest lead on Sally's killer, Tosh arrives in Norway, leaving Perez following up the leads on the Kilmuir case. Tosh accesses the CCTV from the airport and sees footage of Sally leaving the terminal, discovering she had met with a man who has far-right associations.

The hunt is on for Malone's attacker, Malone seems to know who is responsible, but isn't keen to share the information. Perez and Rhona believe Andreas Hagan, the health and safety officer at Forst Energy isresponsible for covering up corporate manslaughter and is their strongest lead in Sally McColl's murder. Meanwhile, DNA testing in the Kilmuir case yields a surprising result.