Invited to join a new police CID team in the South of England, DCI Jon Pilgrim joins the SIU: a unit of detectives specializing in hunting the most dangerous kinds of criminal. Jon and his team must deal with cruel murderers, seductive femme fatales, and dark secrets to crack the cases and saves the lives of the innocent.

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.

When the chief suspect in the notorious Peek-a-boo 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 Peek-a-boo fashion, Bone is persuaded to return to lead the new investigation. But as Bone and his team hunt a copycat killer, and with time running out before yet another cop is slain, Bone’s terrifying past returns to tear open old wounds and push him to very edge of the abyss.

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.

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.

When a girl’s body is found strangled, raped, and horrifically mutilated by a boat’s propeller, deep in the heart of the Norfolk Broads, newly arrived Detective Inspector John Tanner is asked to assist with the investigation. At first, all the evidence points to a man who had a multi-million-pound reason to kill her. But when an alibi is produced from an unexpected source, and another body appears at the base of a slipway, Tanner finds himself turning to local girl Detective Constable Jenny Evans for help.

A body is discovered deep in a cave beneath the Yorkshire Dales. Leading the investigation into the mysterious death are experienced DCI Jim Oldroyd and his partner DS Carter, a newcomer from London. The deceased is Dave Atkins, well known throughout the village but not well liked. While there is no shortage of suspects, the details of the crime leave Oldroyd and Carter stumped.

Haunted by his inability to track down and save his missing wife, DCI Robert Kett leaves the Metropolitan Police behind and moves to Norwich with his three young children, hoping to heal their broken family. But his newfound peace doesn’t last. Two newspaper delivery girls have gone missing in the city, and the clues point to a serial kidnapper. Kett is dragged into the centre of one of the darkest cases of his career - a case that pits him head-to-head against a horrifying evil.

A sinking boat is spotted off the South Coast. Waiting onboard is a grisly discovery. DCI Boyd, recently relocated from London to Hastings, is now with the East Sussex CID, and his first case is that of a local businessman and his new young wife, missing in the English Channel. All that remains of them is a grim scene aboard their half-submerged yacht and a digital trail of clues that could put Boyd and his daughter, Emma, in danger.

Crimebusting duo DI Jackman and DS Evans are back, solving another crime that will make your skin crawl. Twenty years ago: a farmer and his wife are cut to pieces by a ruthless serial killer. Now: a woman is viciously stabbed to death in the upmarket kitchen of her beautiful house on the edge of the marshes. Then a man called Daniel Kinder walks into Saltern police station and confesses to the murder. But DI Rowan Jackman and DS Marie Evans of the Fenland Constabulary soon discover that there is a lot more to Daniel than meets the eye.

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.

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.

DI Nikki Galena: A police detective with nothing left to lose, she's seen a girl die in her arms, and her daughter will never leave the hospital again. She's gotten tough on the criminals she believes did this to her. Too tough. And now she's been given one final warning: make it work with her new sergeant, DS Joseph Easter, or she's out.

Criminologist Martin Knight lives a gilded life and is a thorn in the side of the police. But then his wife, Liz, goes missing. There is no good explanation and no sign of Martin.... To make things worse, Liz is the ex-girlfriend of DCI Craig Gillard who is drawn into the investigation. Is it just a missing person or something worse? And what relevance do the events around the shocking Girl F case, so taken up by Knight, have to do with the present? The truth is darker than you could ever have imagined.