The Island

When the matriarch of the well-known Maclean family is murdered, PC Kat Crichton returns to the Isle of Harris to take on the case; after unexpected personal connections complicate her investigation, she finds herself confronting the past.

Kat flags inconsistencies in Sir Douglas's story, but without proof, suspicion falls on the Macleans' son, Calum; as secrets surface, Sine sets out to find her mother's diary, which may hold clues to her murder; a shocking confession comes to light.

As Halim starts to wrap up the case, Kat believes there's more to the story and pushes on; at Lady Mary's wake, Kat uncovers a dark family secret, but a sudden allegation derails everything; Ruaraidh's charred diary hints at a betrayal.

After a family secret is revealed, Calum vanishes, and the siblings reflect on their father's involvement in their lives; Sir Douglas and Kat finally come face to face, as she confronts the demons of her past to bring Lady Mary's killer to justice.