Acclaimed murder-mystery drama Shetland returns for a tenth series as Calder and Tosh are drawn to a remote village following the sinister murder of an elderly woman. As they begin to unravel life in this close-knit community, shocking, long-buried secrets rise to the surface with unexpected consequences for all β including the team. In the isolated hamlet of Lunniswick, the body of the retired social worker Eadie Tulloch has been out in the elements for a number of days. Suspecting the residents are holding back about their relationships with Eadie, Calder and Tosh begin to unravel a complicated web of lies. Worse still, there's a personal link to the case for one of the team, testing loyalty to the limits.

Calder and Tosh travel to the remote village of Lunniswick to investigate the brutal murder of an elderly woman. She has been out in the elements for several days.

In the aftermath of the fire, Tosh and Calder struggle to get answers from an unreliable suspect. A historic grudge from Eadie's time as a social worker comes to light.

Events in Lunniswick turn violent as holidaymakers Chris and Hayley risk it all to clear their debts. A paranoid Stevie wants Amy all to herself.

While Calder pressures Louden for help and Tosh investigates Robert Tulloch, Stevie's battle to keep her sister turns desperate.

Tosh finally confronts Billy about his relationship with Robert Tulloch. Fuelled by guilt over Louden, Calder goes after the people responsible.

As Calder and Tosh close in on the motive for Eadie's murder, the pool of suspects narrows.