Marnie Bruce has hyperthymesia; she can remember everything she has ever seen. Everything except from one fateful night when she was eleven; she woke up in an isolated cottage with a head injury and her mother gone. Twenty years later Marnie heads back to Scotland seeking answers to what happened, but in the small town of Galloway, her mother's disappearance still burns in the air and Marnie's return looks set to tear open old wounds for many of the locals.