High-flying financiers are being murdered and it is beginning to appear like the work of a serial killer.

A special police unit is set up after three businessmen are murdered over three consecutive nights. Detective Jenny Hultin leads the so-called A Unit to investigate the killings while the financial world panics.

An American serial killer is on board a plane from New York to Stockholm. Without a proper identification and with great urgency, A Unit try to locate him before Sweden inadvertently imports a killer whose methods are bloodthirsty and can be traced back to the Vietnam War.

A Unit continue to hunt for the Kentucky Killer, the infamous American serial killer who is now on the loose in Sweden.

A Swedish family is on a road trip in Holland when their car is blown apart in a violent explosion. The man, woman and young child are killed instantly.

Nyberg has been helping child abuse investigator Sara Svenhagen chase a paedophile ring and is disturbed by what they find. Chavez takes an instant shine to Nyberg\'s new colleague and soon finds himself in romantic complications.

When an illegal African immigrant is shot and killed by police, Kerstin Holm is assigned the task of interviewing the police officer.

\'A Unit\' discovers a link between the shooting of an illegal African immigrant, bodies found in a marsh in Varmland and an apparent suicide.

Celebrated Jewish neuroscientist Leonard Sheinkman is found murdered, strung up from a tree in a Jewish cemetery. A group of women escape from an immigration board hostel, where they are being exploited as prostitutes, and flee the country.

In pursuit of leads to help with the wolverine murder, Soderstedt is despatched to Italy where he encounters a dangerous Mafia boss. Soon he finds himself in Germany following up leads from the murdered Leonard Sheinkman\'s war diaries, while also trying to unravel the mystery of the inheritance he has received from his uncle.