The lives of DI Cadi John and DS Owen Vaughan are shaken by the discovery of the body of a young woman on the banks of a river. As they discover the girl's identity, it seems she may be just one of a number of young women to go missing in the area. What secrets are lurking in this spectacular area of North West Wales?

The police investigation enters a new phase when DI Cadi John and DS Owen Vaughan are called to the scene of a potential kidnapping in the middle of the night, and their concerns that a serial kidnapper is on the loose are confirmed, but a shocked Lowri Driscoll isn't able to offer any information about the identity of her attacker