Met cop DI Rob Marshall is hot on the trail of the serial killer known as the Chameleon, who has abducted, tortured and killed a series of young women in Northwest London. As they close in, the Chameleon—who switches identity to get close to his victims—shoots Marshall’s partner and escapes.

Ailsa Connolly was a brilliant psychologist and a respected criminologist. She was also a serial killer. Six years ago, DCI Sean Bracken caught her just before he was about to become her seventh victim. Every year on the anniversary of her incarceration, she taunts him with a phone call, giving him one message: "When I get out, I'll kill you." Now, Bracken has transferred back to Edinburgh and is thrown into the deep end on his first day back on duty. There's a killer who is emulating Ailsa, threatening to surpass her body count.

The head of Scotland’s most powerful crime family is brutally murdered, his body dumped inside an ancient grave in a remote cemetery. Detectives Max Craigie and Janie Calder arrive at the scene, a small town where everyone has secrets to hide. They soon realise this murder is part of a blood feud between two Scottish families that stretches back to the 1800s. One thing’s for certain: it might be the latest killing, but it won’t be the last.

A mutilated body is found dumped at Cowane's Hospital in the heart of historic Stirling. For DCI Malcolm Ford it's like nothing he's ever seen before, the savagery of the crime making him want to catch the murderer before he strikes again. For reporter Donna Blake it's a shot at the big time, a chance to get her career back on track and prove all the doubters wrong. But for close protection specialist Connor Fraser it's merely a grisly distraction from the day job.

While her parents are just yards away, thirteen-month-old Lily Hamilton is abducted from Ayr beach in Scotland. Three days later, her distraught father turns up at private investigator Charlie Cameron's office. Mark Hamilton believes he knows who has taken his daughter. And why. Against his better judgment, Charlie takes the case—and when bodies are discovered, he suspects this may not be an isolated crime. Is there a serial killer whose work has gone undetected for decades? Is baby Lily his latest victim?