Oliver Peterkinney and Alex Glass, two friends from Glasgow's desperate fringes, become involved in one of the city's darkest and most dangerous trades: debt collection. While one rises quickly through the ranks, the other falls prey to the industry's addictive lifestyle, accumulating steep debts of his own.

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?

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.

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.

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.

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.

Former soldier. Ex-copper. Current man on the edge. Shunned by his old colleagues, and dividing his time between a dead-end job and the bottom of a whisky bottle, former Police Scotland detective superintendent Bob Hoon’s life is a mess. Then an old face from Hoon’s Special Forces days turns up asking for help: His teenage daughter has been missing for months, the police have drawn a blank, and he needs the kind of help that only Hoon can provide. And besides, Hoon owes him one.

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.

The story opens with the apparently accidental drowning of a sixth form student in the Norfolk countryside. As a matter of routine, or so it seems, the case passes across the desk of Detective Sergeant Smith, recently returned to work after an internal investigation into another case that has led to tensions between officers at Kings Lake police headquarters. As an ex-DCI, Smith could have retired by now, and it is clear that some of his superiors wish that he would do so.

It is 1969 and Glasgow is in the grip of the worst winter in decades, yet it is something else that has Glaswegians on edge: a serial killer whose name alone is enough to make them tremble with fear. The Quaker has killed another victim, snatching a young woman from a nightclub and dumping her body like trash in the back of a cold-water tenement. He leaves no clues, and the investigation has led police down one blind alley after another.

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.

This is a fact: Ryan Summers walked into Three Rivers College and killed 13 women, then himself. But no one can say why. The question is one that cries out to be answered - by Ryan's mother, Moira; by Ishbel, the mother of Abigail, the first victim; and by DI Helen Birch, put in charge of the case on her first day at her new job. But as the tabloids and the media swarm, as the families' secrets come out, as the world searches for someone to blame...the truth seems to vanish.

Northern Ireland, spring 1981. Hunger strikes, riots, power cuts, a homophobic serial killer with a penchant for opera, and a young woman’s suicide that may yet turn out to be murder: on the surface, the events are unconnected, but then things—and people—aren’t always what they seem. Detective Sergeant Duffy is the man tasked with trying to get to the bottom of it all. It’s no easy job—especially when it turns out that one of the victims was involved in the IRA but was last seen discussing business with someone from the loyalist Ulster Volunteer Force.

Ten strangers are lured to an isolated island mansion off the Devon coast by a mysterious "U.N. Owen". At dinner a recorded message accuses each of them in turn of having a guilty secret, and by the end of the night one of the guests is dead. Stranded by a violent storm, and haunted by a nursery rhyme counting down one by one...one by one they begin to die. Who among them is the killer? And will any of them survive?

When a landslip on Pembrokeshire’s stunning coastal path reveals the harrowing remains of two bodies, ex-DCI Evan Warlow’s quiet retirement is shattered.