They are hunting for an invisible killer - so secretive and elusive that only a series of terrible crimes proves his existence... A car found in an abandoned pond. The bodies of two girls lying in the back seat. The mysterious absence of their mother, who disappeared without a trace. Accident - or murder? Solving this mystery could cost Gwen Proctor and her friend, police officer Kezia Clairmont dearly... At first glance, everything is fine in Gwen's life. Her two children and her beloved man are nearby, and all the nightmares and horrors are a thing of the past. But it is Gwen's dark past that haunts someone invisible... and unstoppable. To those who want to get to her - and face a terrible choice...