On an ordinary February evening in 1986, Prime Minister Olof Palme was murdered. And almost 30 years later, Jan Stocklassa finds some boxes in a storage room. The boxes contain author Stieg Larsson's own investigation of the Palme murder.
When the boxes are unpacked, the picture of Palme's enemies becomes clearer. In Larsson's investigation, there are both Cold War traces and a mapping of extremists - where three individuals stand out. Could one of them murdered Palme?
The search for answers takes Stocklassa to a new continent and an unexpected motive. Convinced that Stieg was up to something, he manages to talk to two South African agents who admit that attacks were carried out in Europe.
While Jan ties up the loose ends of Stieg's investigation, he becomes increasingly reckless in his search. And 2ith new information, Jan reports to the official Palme investigation and suddenly Swedish police call a press conference.