Denmark is the midst of a fiercely contested election race, set against the backdrop of the financial crisis. With ten days to go to the election, Detective Chief Inspector Sarah Lund prepares to celebrate her 25th year in the police force and looks forward to the prospect of a new job in the force. But her relative peace is shattered when body parts are found at Copenhagen dock only hours before a scheduled visit by the prime minister.

A new element turns out to play a role of great significance in the investigation. Borch and Lund have a hard time shaking off their Jutland experience, and their working relationship suffers as a result. Robert and Maja harbour hopes that Emilie may still be alive and Zeeland throw all their resources into tracking her down, as a secret is revealed from an unlikely source within the family. Police run checks on Ussing's movements over the last couple of years.

A suspect is taken in for examination as the police try to find out more about the notebook they discovered, but things go less than smoothly. The prime minister and his close aids become the focus of police attention, as Karen is also found to be hiding a dangerous secret which could prove fatal for the government. Borch and Lund's trip to Jutland begins to have consequences. Robert Zeuthen intensifies the hunt for his daughter, despite coming under heavy pressure from the Zeeland board. Maja takes sides. A witness turns up who may have important information about Emilie.

Sarah Lund is held back in her attempts to make headway with the investigation, but at least the perpetrator finally has a face. Will he lead police and the Zeuthens to Emilie? Prime Minister Kamper is trying to clean up his circle as he attempts to find out what happened to his son. Suspicions arise about a trusted Zeeland figure as Robert Zeuthen considers drastic action.