When the body of Mali Pryce is discovered in a river in the Snowdonia National Park, DI Cadi John and DS Owen Vaughan are brought together to try and piece together the location and movements of the deceased in the years following her disappearance in 2011. The discovery of the body opens old wounds in the community, and Mali’s father is furious with what he sees as police ineptitude. District nurse Lowri Driscoll battles with the unwanted attention of her ex-boyfriend, while Cadi tackles her own personal problems as she deals with her father Huw’s failing health and family arguments with her sisters. The strange relationship between Dylan Harris and his mother Iona reaches crisis point.