1813. Haunted by her father's death and tired of watching her mother struggle, Meg Marsh will do anything to keep a roof over her family's head. Even if that means getting involved in a dangerous smuggling operation.

When Meg catches the eye of a dashing gentleman above her station, things start to look up, and she can't help but start dreaming of a life away from the shingle and boats of Castle Bay. Blinded by flattery and coin, Meg can't see the danger on the horizon - and the cost just might be her life.

1913. Carrie Marsh lives a quiet life as a teacher until she falls in with the wealthiest family in Castle Bay and turns the head of the charming eldest son, Oscar.

In an attempt to impress her new friends, she takes them to the secret garden rumoured to be haunted by her murdered ancestor. One outing turns into a carefree summer of pleasure, and the garden becomes a hideaway for Oscar and Carrie.

But when they accidentally stumble upon human bones, Carrie is forced to ask herself whether she really knows Oscar at all - and whether she is doomed to follow in her ancestor's footsteps.