Adapted from Ann Cleeves celebrated novels, Shetland series 4 is an original story which sees DI Jimmy Perez deal with murders from the past and present with unsettling similarities.
When Shetlander, Thomas Malone (played by Stephen Walters) has his murder conviction overturned after 23 years behind bars, DI Perez has to reopen the investigation into the 1994 death of local teenager, Lizzie Kilmuir.
As suspicion surrounds Malone, a local journalist is found murdered in similar circumstances and he finds himself firmly in the frame again. Has Malone fooled the system in to releasing him only to murder again? Or was he a victim of a miscarriage of justice? As pressure mounts on Perez, he must look beyond the gossip and prejudice to get to the truth.
Douglas Henshall returns in the lead role of DI Jimmy Perez for Series 4.
New cast who have joined Shetland for this series include Neve McIntosh (The Replacement, Doctor Who), Sean McGinley (The Fall, Gangs of New York), Stephen Walters (The Accused), Gerard Miller (Bladerunner, River City), Allison McKenzie (Line of Duty, River City) and Michael Moreland (Filth, Scot Squad).
Perez is played by Douglas Henshall, Thomas Malone by Stephen Walters, Tosh by Alison O’Donnell, Sandy by Steven Robertson, Drew McColl by Sean McGinley, Sally McColl by Amy Lennox, Alan Killick by Gerard Miller, Jo Halley by Sophie Stone, Kate Kilmuir by Neve McIntosh. Also starring Mark Bonnar as Duncan, Erin Armstrong as Cassie, Julie Graham as Rhona.
In tonight's sixth and final episode, as Shetland reaches its thrilling conclusion, the personal and the professional collide for Perez, as he finally closes in on the truth.
Troubled by historical DNA evidence results, Perez has to face the fact that Duncan may have been involved in Lizzie Kilmuir’s murder and potentially Sally McColl’s as well.
A shocked Duncan is brought to the station for questioning, hurt that Perez would even think him capable of murder. However, Perez knows Duncan’s lying - perhaps not about the murder, but about something else significant.
Cassie seeks reassurance from Perez that Duncan isn’t a double murderer, something he’s unable to give his step-daughter.
As things look increasingly bleak for Duncan, an old photo on Sally McColl’s memory stick sheds new light on the investigation and puts another suspect firmly in the frame for Lizzie’s murder.
However, just as Perez begins to close in on the truth, he gets a call from McCabe at the police station. Malone has been seen out walking on the High Street, armed with a shotgun, seemingly hell-bent on revenge and justice.
Shetland airs tonight at 9PM on BBC One.