Mia questions Teddy and Harry, with conflicting results. An arson attempt fuels Mia's suspicions that she is not welcome. The realisation that she hardly knew Cassy draws Mia closer to Ewan.

The town's Whitebait Festival proves the worst possible drug comedown for a strung-out Mia. The truth about her deadly past in Scotland is revealed, yet she remains unrepentant.

With Sadie's help, Mia digs into an earlier death. Meanwhile, Annot recalls more of Ewan's misbehaviour than he would like, and a gruesome discovery in the forest puts Mia in immediate danger.

A deadly hike up the ridge reveals that Mia and Ewan have more in common than expected. While addiction may be a weakness, it gives Mia strength to bring down her sister's killer.