Tosh confronts Billy about Robert Tulloch. Calder retraces Louden’s steps.

Struggling to stay ahead of her actions, Stevie begins to unravel.

Everything unravels as Chris and Hayley’s bid for freedom goes horribly wrong.

As Lunniswick reels from the fire, the team struggle to identify a motive.

The body of an elderly woman is found in the remote village of Lunniswick.

All eyes are on Lisa Friel, until a shocking accusation turns the case on its head.

The chase is on to locate Rossi before he tracks down Annie’s killer.

As Astrid Jakobson disappears, the team uncovers the truth behind the facility’s facade.

The revelation of Annie’s past shifts the investigation into unknown territory.

The search is on for Ian as Calder and Tosh dig into Annie and Bergen’s relationship.

When a woman goes missing with her young son, Tosh and Calder set out to find them.

Calder and Tosh reunite as the police descend upon the Bain farm and begin their search.

As Calder reels from the devastating news, Tosh follows a controversial line of enquiry.

Tosh believes she has the murderer. Calder struggles with Jean’s revelation.

The discovery of a tattoo sends the case in a sinister new direction.

Calder and Tosh must work together to find the armed killers and prevent further disaster.

A Met detective returns to Shetland on the trail of a vulnerable witness.

The team races to identify the killer and prevent disaster striking Lerwick.

Perez tries to get the measure of Lloyd. Evidence emerges of another bombmaker.

Perez issues a warrant for Connor’s arrest and looks for the motive for his bomb-making.

Mounting evidence pushes Perez and the team to revise their view of Connor Cairns.

As the search for Connor grows desperate, Perez follows Danny on a journey into his past.

DI Perez investigates the mysterious disappearance of a vulnerable young man.

Perez must put Duncan out of his mind as he closes in on Galbraith’s killer.

The search for Galbraith’s killer leads Perez and Tosh to the remote island of Fetlar.