Chief of Investigation of Unit One, Torben Rønne, is found murdered in his house along with Henning Ravn, a friend of his who was temporarily living at Torben's. Ingrid Dahl is promoted to temporary Chief of Investigation to support Unit One. Because of information provided by a criminal, Unit One locates Dennis Friis, the son of a woman Ravn used to date years back. As Friis tries to pick up the murder weapon, he is discovered by Fischer and La Cour and taken into custody. He confesses the crime under questioning with Dahl.

A bar owner is executed in the woods. The deceased was discovered after being liquidated. He also has outstanding business with the local bikers. But Ingrid thinks the motive for the homicide is more of a personal nature. The larger mobile office is put to use for the first time and its driver proves to be a surprise. Just as the investigation gets underway Ingrid receives a phone call that forces her to rush back to Copenhagen.

Fischer and La Cour find Grue, the biker president, who is carrying a sawn-off shotgun around which resembles the murder weapon from their case. But the revelation that follows is not what they expected. Ingrid Returns with a plan that conflicts with Chief Constable Ulf Thomsen. Fischer receives unexpected help when he gets into a fight with a couple of suspects. La Cour finds a vital clue and IP suspects something going on between Gaby and Johnny Olsen.

When an elderly lady is murdered in Nakskov, details emerge from her younger female lodger, who says she saw an unfamiliar man leave the house just after the crime. Fischer's relationship with the local force is complicated because of a previous case and the conflict between them resurfaces. IP is worried about Kirsten's whereabouts, and Ingrid's husband Søren surprises her just as she is on her way out with Boysen.

A young couple's wedding day is ruined by a murder. The killing seems unfeasible and the forensics experts are perplexed when Unit One arrives. Soon, many of the villagers are under suspicion. While IP's jealously grows, Johnny receives help from Gaby with his personal problems. Søren puts pressure on Ingrid to make a decision about their relationship. But all could be futile when Ingrid soon after receives a phone call from the hospital alerting her that Søren is in a serious condition.

Ulla, a teacher from Roskilde, has celebrated her 30th birthday with a big party among friends and relatives. On her way home from the party, she disappears without a trace. Her husband calls the police and Unit One is summoned. Evidence indicates that a crime has taken place, and Ulla's children also face danger. Ingrid is in an awful state following Søren's death and has incarcerated herself. Gaby and Johnny try to help but in vain. However, IP has his own way of tackling Ingrid. Fischer receives a tempting offer from Ulf.