Carl Mørck, the former head of Department Q, comes across a disturbing audio recording and turns it over to his former colleagues, who are struggling to keep the old department up and running on their own. That is, until a new transfer unexpectedly arrives --- Helena Henry, a Frenchwoman who throws herself into the investigation with gusto, but who may also have secrets of her own. When the team realizes that the audio recording might shed new light on a supposedly open-and-shut murder-suicide case from years earlier, suddenly everything they thought they knew is called into question. Meanwhile, a spurt of seemingly random violence leads the Department Q team to investigate a possible connection to a different long-ago dark and sinister event.

When the head of Department Q, Detective Carl Mørck, finds himself handcuffed in a police car headed for Copenhagen's Vestre prison, he realizes that a violent case from his past has finally caught up with him. But he is being framed. Someone has a million-dollar bounty on his head to make sure he doesn't talk, putting him in grave danger among the prison's incarcerated criminals and corrupt officers. Carl's colleagues at the Copenhagen Police Department instantly turn their backs on him, leaving the ever-loyal Department Q team as his only hope. With only one another to trust and Carl's battle against the unknown mastermind's henchmen worsening by the day, they must work faster than ever before if they are to clear his name --- and save his life.

On her 60th birthday, a woman takes her own life. When the case lands on Detective Carl Mørck’s desk, he can’t imagine what this has to do with Department Q, Copenhagen’s cold cases division, since the cause of death seems apparent. However, his superior, Marcus Jacobsen, is convinced that this is related to an unsolved case that has been plaguing him since 1988. At Marcus' behest, Carl and the Department Q gang reluctantly begin to investigate. And they quickly discover that Marcus is onto something: Every two years for the past three decades, there have been unusual, impeccably timed deaths with connections between them that cannot be ignored. As the investigation goes deeper, it emerges that these "accidents" are in fact part of a sinister murder scheme.

The newspaper refers to the body only as Victim 2117 --- the 2,117th refugee to die in the Mediterranean Sea. But to three people, the unnamed victim is so much more, and the death sets off a chain of events that throws Department Q, Copenhagen’s cold cases division led by Detective Carl Mørck, into a deeply dangerous --- and deeply personal --- case. A case that not only reveals dark secrets about the past, but has deadly implications for the future.

Democratic Senator Bruce Jansen has been elected president of the United States. For 14-year-old Dorothy "Doggie" Rogers, Jansen's election is a personal victory: a job in the White House, proof to her Republican father that she was right to support Jansen, and the rise of an intelligent, clear-headed leader with her same ideals. But the triumph is short-lived: Jansen's pregnant wife is assassinated on election night, and the alleged mastermind behind the shooting is none other than Doggie's own father. When Jansen ascends to the White House, he is a changed man, determined to end gun violence by any means necessary. With the country in chaos, Doggie finds herself fighting for the life of her father, who just may be innocent.

In a Copenhagen park, the body of an elderly woman is discovered. The case bears a striking resemblance to another unsolved homicide investigation from over a decade ago, but the connection between the two victims confounds the police. Across town, a group of young women are being hunted. The attacks seem random, but could these brutal acts of violence be related? Detective Carl Mørck of Department Q is charged with solving the mystery. Meanwhile, after an earlier breakdown, their colleague Rose is still struggling to deal with the reemergence of her past --- a past in which a terrible crime may have been committed. It is up to Carl, Assad and Gordon to uncover the dark and violent truth at the heart of Rose’s childhood before it is too late.

Carl Mørck has no choice but to lead Department Q into the tragic cold case of a vivacious 17-year-old girl who vanished from school, only to be found dead hanging high up in a tree. The investigation will take them from the remote island of Bornholm to a strange sun-worshipping cult, where Carl, Assad, Rose and newcomer Gordon attempt to stop a string of new murders and a skilled manipulator who refuses to let anything --- or anyone --- get in the way.

Due to their deception, British pilots James Teasdale and Bryan Young end up in the Alphabet House, a mental hospital where German doctors subject their patients to daily rounds of shock treatments and experimental drugs. Their only hope of survival is to fake insanity until World War II ends, but their friendship and courage are put to the ultimate test when James and Bryan realize they aren’t the only ones in the Alphabet House feigning madness.

All 15-year-old Marco Jameson wants is to become a Danish citizen and go to school like a normal teenager. But his uncle Zola forces the children of his gypsy clan to beg and steal for his personal gain. When Marco discovers a dead body, he goes on the run. Meanwhile, the last thing Detective Carl Mørck needs is for his assistants to pick up a missing persons case on a whim. But when he learns that a mysterious teen named Marco may have as much insight into the case as he has fear of the police, Carl is determined to solve the mystery and save the boy.

In 1987, Nete Hermansen plans revenge on those who abused her in her youth, including Curt Wad, a charismatic surgeon who was part of a movement to sterilize wayward girls in 1950s Denmark. More than 20 years later, Detective Carl Mørck is presented with the case of a brothel owner named Rita, who went missing in the ’80s. As he and his assistants sift through the disappearances, they get closer and closer to Curt, who is more determined than ever to see the vision of his youth take hold.

Detective Carl Mørck holds in his hands a bottle that contains an old and decayed message, written in blood. It is a cry for help from two young brothers, tied and bound in a boathouse by the sea. Who are these boys, and why weren’t they reported missing? Carl’s investigation will force him to cross paths with a woman stuck in a desperate marriage. He and his colleagues must use all of their resources to uncover the horrifying truth.

Detective Carl Mørck is intrigued when a closed case lands on his desk: A brother and sister were brutally murdered two decades earlier, and one of the suspects --- part of a group of privileged boarding-school students --- confessed and was convicted. But once Mørck reopens the files, it becomes clear that all is not what it seems.

After a bullet almost takes his life, former homicide detective Carl Morck is put in charge of sorting through a stack of Copenhagen's cold cases. To his surprise, he finds that a case of a missing politician actually captures his interest, because she isn't dead...yet.