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. 

A woman is found in a local cemetery, crushed to death under a gravestone. A production company is there, filming the remake of a classic sci-fi TV show on the grounds, making the investigation more difficult for DCI Harry McNeil. It's his first day in charge of the cold case unit in Edinburgh. After spending four years in Professional Standards, he has little choice but to take the promotion.

Meet Simon Fenchurch, detective inspector working the Met’s East London beat. Honest and funny but damaged, he’s working a case that could give him answers to his deepest trauma....

Was the biggest case of his career the worst mistake he ever made? Ten years ago, DCI Jack Logan stopped the serial child-killer dubbed "Mister Whisper", earning himself a commendation, a drinking problem, and a broken marriage in the process...When another child disappears a hundred miles north in the Highlands, Jack is sent to lead the investigation and bring the boy home. But as similarities between the two cases grow, could it be that Jack caught the wrong man all those years ago?

Detective Chief Inspector Harry Grimm is forced to take leave from Bristol’s Major Investigations Team when his boss, tired of Harry chasing the ghost of his murderous father, sends him north on secondment. Used to city life and high stress, Harry fears his life will now be spent handing out speeding tickets, finding lost sheep, and directing tourists. But when a local teenager runs away, Harry finds himself pulled into an investigation much worse than anyone could have ever expected.

D.I. Duncan McAdam is dispatched home to the Misty Isle. A body has been found buried in a remote location on the Waternish peninsula. Well-preserved in the peat, Isla Matheson—missing for the better part of two decades—is revealed to a shocked island community. A teenage runaway is dead...and no one is talking.

When a 15-year-old girl fails to make it home after school, DI Heather Filson believes she’s dealing with just another teenage runaway. The girl’s grandfather, a notorious Glasgow gangster, disagrees. Convinced one of his underworld enemies has grabbed her, he’s prepared to bathe the city in blood in order to bring his princess home.

In the shadow of the Pentland Hills, a man has been callously struck down in front of his home. Tyre marks suggest it was no accidental hit-and-run. Somebody wanted him dead and as the man fights for every breath, they might still get their wish. Grappling with the demons he thought he could leave behind after months away on enforced leave, D.S. Malkie McCulloch resists pressure from his superiors to pass the case on to the road policing unit, convinced that whoever was behind the wheel will be waiting for the chance to finish the job.

When the chief suspect in the notorious "peekaboo cop killer" case blew himself up, almost taking lead investigator DCI  Duncan Bone with him, the psychologically damaged detective thought his days on the force were over. But, when another PC is abducted and murdered in the same deranged peekaboo fashion, Bone is persuaded to return to lead the new investigation.

Five years ago, DCI John Lomond led the search for notorious Glasgow child-killer ‘The Sandman', until personal tragedy forced him off the case. In Lomond's absence, the killer was never found. Now, with nothing but work left in his life, Lomond remains obsessed with the case–despite the nightmares it brings. When a child is abducted in similar Sandman fashion from an affluent Glasgow suburb, Lomond is brought in to find them before it's too late.