A shocking double-murder scene greets Detective Inspector Philip Brennan when he is called to a flat in Colchester. Two women are viciously cut open and laying spreadeagled, one tied to the bed, one on the floor. The woman on the bed has had her stomach cut into and her unborn child is missing. But this is the third time Phil and his team have seen such an atrocity. Two other pregnant women have been killed in this way and their babies taken from them. No-one can imagine what sort of person would want to commit such evil acts. When psychologist Marina Esposito is brought in, Phil has to put aside his feelings about their shared past and get on with the job. But can they find the killer before another woman is targeted?

Suzanne Perry is having a vivid nightmare. Someone is in her bedroom, touching her, and she can't move a muscle. She wakes, relieved to put the nightmare behind her, but when she opens the curtains, she sees a polaroid stuck to the window. A photo of her sleeping self, taken during the night. And underneath the words: 'I'm watching over you'. Her nightmare isn't over. In fact, it's just beginning. Detective Inspector Phil Brennan of the Major Incident Squad has a killer to hunt. A killer who stalks young women, insinuates himself into their lives, and ultimately tortures and murders them in the most shocking way possible. But the more Phil investigates, the more he delves into the twisted psychology of his quarry, Phil realises that it isn't just a serial killer he's hunting but something? or someone? infinitely more calculating and horrific. And much closer to home than he realised…

Workers demolishing a building in Colchester make a horrifying discovery in the basement: a cage made of human bones…with a feral child inside. As Phil Brennan and Marina Esposito investigate, they expose the trail of a serial killer who has been operating undetected for thirty years – a killer with a disturbing connection to Brennan's father

Detective Inspector Phil Brennan and criminal psychologist Marina Esposito have just returned from their honeymoon and are spending the Easter weekend in Suffolk with their baby daughter Josephina and Phil's adoptive parents. But their rural idyll is cruelly destroyed. After a devastating arson attack on the cottage, Josephina goes missing. With Phil in a coma, Marina is alone when she receives the first phonecall.The kidnappers say that if Marina ever wants to see her daughter alive again, she has to do exactly what they say…