<Tr> <Td_colspan="7"> Perez and the team discover that the person responsible for the deaths of Robbie Morton and Michael Thompson is closer to home than they had thought . </Td> </Tr> <P> The broadcast of Episode 3 was delayed by 24 hours due to the broadcast of an FA Cup replay . </P> <Table> <Tr> <Th> Overall No . </Th> <Th> Episode No . </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> UK air date </Th> <Th> UK viewers (million) </Th> </Tr> <Tr> <Th> 15 </Th> <Td> </Td> <Td> "Episode 1" </Td> <Td> Lee Haven Jones </Td> <Td> David Kane </Td> <Td> 13 February 2018 (2018 - 02 - 13) </Td> <Td> 6.72 </Td> </Tr> <Tr> <Td_colspan="7"> Perez and the team are forced to re-open a twenty - three year old cold case when convicted murder, Thomas Malone, is released from prison . The case concerns teenager Lizzie Kilmuir, who was found strangled to death on a kiln . Upon returning to Shetland, Thomas tries to make amends with Lizzie's elder sister, Kate . Meanwhile, local journalist Sally McColl attends the Shetland Folk Festival with a group of her friends, but doesn't return home later that evening . The next day, she is found strangled to death on a kiln, in what looks like a copycat of Lizzie's murder . Perez is forced to break the news to Drew, Sally's father and a former police officer who lead the investigation into Lizzie's murder . </Td> </Tr> <Tr> <Th> 16 </Th> <Td> </Td> <Td> "Episode 2" </Td> <Td> Lee Haven Jones </Td> <Td> Louise Ironside </Td> <Td> 20 February 2018 (2018 - 02 - 20) </Td> <Td> 6.28 </Td> </Tr> <Tr> <Td_colspan="7"> Perez sets out to find out who attacked Thomas . Sandy interviews Jo Halley, who claims she saw Sally arguing with someone in Norwegian at the folk festival . Tosh interviews employees at Forst energy, a Norwegian company whom Sally was investigating shortly before her death . Perez orders a DNA test on a previously untested hair found on Lizzie Kilmuir's scarf . </Td> </Tr> <Tr> <Th> 17 </Th> <Td> </Td> <Td> "Episode 3" </Td> <Td> Lee Haven Jones </Td> <Td> Paul Logue </Td> <Td> 28 February 2018 (2018 - 02 - 28) </Td> <Td> 6.08 </Td> </Tr> <Tr> <Td_colspan="7"> Tosh heads to Norway to track down the mysterious Andreas Hagan, where she meets detective Lars Bleymann, who takes an instant shine to her . Finding herself drawn into a murky world of far right campaigners, Tosh is alarmed when she returns to her hotel room later that night and finds someone going through her belongings . Perez interviews Donna after receiving the results of the DNA test . </Td> </Tr> <Tr> <Th> 18 </Th> <Td> </Td> <Td> "Episode 4" </Td> <Td> Rebecca Gatward </Td> <Td> David Kane </Td> <Td> 6 March 2018 (2018 - 03 - 06) </Td> <Td> 5.31 </Td> </Tr> <Tr> <Td_colspan="7"> Perez and Tosh find themselves being pursued by the secret service as their investigation in Norway continues, but when their prime suspect, Mathias Soderland, is found shot in the head whilst bearing a sign reading' traitor', they are forced to return to Shetland . Perez questions Duncan about a videotape of a birthday party which Lizzie attended in the days before her death, in which he was present . Sandy receives a distress call from Jo Halley and arrives at her croft to find it has been ransacked . </Td> </Tr> <Tr> <Th> 19 </Th> <Td> 5 </Td> <Td> "Episode 5" </Td> <Td> Rebecca Gatward </Td> <Td> David Kane </Td> <Td> 13 March 2018 (2018 - 03 - 13) </Td> <Td> TBA </Td> </Tr> <Tr> <Td_colspan="7"> Tosh begins to question if Lars could somehow be involved in Sally's murder after picking up that he knew about roadworks that took place on the island a week before he arrived . A review the CCTV footage of Sally arriving in Norway reveals that her keychain holds a memory stick which contains video footage of Lars attending an NDA meeting . Under scrutiny, Lars claims that he was witness to the argument between Sally and another man on the night of her death, but Perez is shocked when Lars identifies Duncan . </Td> </Tr> <Tr> <Th> 20 </Th> <Td> 6 </Td> <Td> "Episode 6" </Td> <Td> Rebecca Gatward </Td> <Td> David Kane </Td> <Td> 20 March 2018 (2018 - 03 - 20) </Td> <Td> TBA </Td> </Tr> <Tr> <Td_colspan="7"> Jimmy realises that he has no choice but to bring Duncan in for questioning . Duncan denies murdering Lizzie and Sally, but does admit to having an affair with Donna Killick . During a review of images found on Sally's memory stick, Sandy finds a picture taken on the Unst Ferry in June 1993, shortly after Lizzie was murdered, that seemingly identifies the killer . When Duncan's DNA matches the sample found on Lizzie's scarf, Jimmy is forced to break the news to Cassie that Allan is her half - brother . After Donna confesses to the murder, Drew MaColl tells Perez that he was trying to protect Donna, and that in doing so he killed his daughter, Sally . Finally clear of both murders, Thomas suffers a fatal heart attack and dies a free man . </Td> </Tr> </Table> <Tr> <Th> Overall No . </Th> <Th> Episode No . </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> UK air date </Th> <Th> UK viewers (million) </Th> </Tr>

When will season 4 of shetland be aired
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