After an elite criminal profiling unit is shut down amid a storm of scandal and mismanagement, only one person emerges unscathed. Forensic psychiatrist Doctor Alexander Gregory has a reputation for being able to step inside the darkest minds to uncover whatever secrets lie hidden there, and soon enough he finds himself drawn into the murky world of murder investigation. In the beautiful hills of County Mayo, Ireland, a killer is on the loose. Panic has a stranglehold on its rural community, and the Garda are running out of time.

There's a serial killer targeting the streets of Newcastle, seemingly picking his victims at random but subjecting them all to the same torturous end. When the Chief Inspector on the case goes missing, it falls on DCI Ryan to track down the man who is brutally murdering women and goading the police to 'catch me if you can'. As everyone becomes a suspect, Ryan and his team get drawn further and further into the case, but for Ryan the nightmare gets closer to home than he could ever have imagined.

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.

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.

DS Whitney Walker wants a promotion, but it’s hard when she’s trying to balance motherhood with a career. When a newborn baby is kidnapped from the local hospital, she draws on her skills as a mother to help. Despite being ordered not to, and when the leads are going nowhere, Walker enlists the help of a local journalist who’s convinced it’s the work of an international baby smuggling ring. Walker’s plan backfires and she fears they’re running out of time.