As Creggan seeks revenge, Perez tries to piece together the events of the previous night.

The hunt is on for Sandy’s attacker, before the investigation takes a horrifying turn.

In the wake of the diving incident, the team searches for a link between the two deaths.

When a prominent local is shot dead on their doorstep, a grieving DI Perez investigates.

Perez closes in on Zezi’s location at last. But can he reach her before it’s too late?

A desperate Olivia tries to get information from Jamie, and the net closes in on McGuire.

Sure that Zezi is being held on Shetland, Perez ups the pressure on his remaining leads.

In the aftermath of Calum’s suicide, Perez travels to Glasgow to try to locate McGuire.

A horrifying discovery at the Hayes house changes the course of the investigation.

A severed hand washes up on a Shetland beach, sparking a complex murder investigation.

The personal and the professional collide for Perez, as he finally closes in on the truth.

Perez must reassess the investigation in the aftermath of the attack.

Ignoring Secret Service warnings, Perez and Tosh track down Mathias Soderland.

The investigation leads Perez and Tosh to Norway and into the world of far-right groups.

Perez hunts Malone's attacker. Tosh suspects a cover-up when she talks to Forst energy.

Thomas Malone returns home to Shetland after spending 23 years in jail for murder.

The murderer of Robbie Morton and Michael Thompson is closer to home than was thought.

Perez struggles to deal with what has happened to Tosh.

Perez and his team are determined to track down the person who helped the killer.

Perez and Tosh go to Glasgow as they try to uncover the reasons behind Maguire's death.

DI Perez is convinced that Michael Maguire is implicated in the death of Robbie Morton.

A young man disappears on the Aberdeen to Shetland ferry crossing.