Spring returns to Sweden's far north, but darkness lies at the heart of the small town of Gasskas. Natural resources in the region are being shamelessly exploited by shadowy multinationals, opposed only by Lisbeth Salander's niece Svala and a group of environmental activists. What begins as a protest spins out of control when a young journalist is found murdered. Journalist Mikael Blomkvist, who has taken a new job at the Gasskas newspaper, starts the investigation and unravels a story that has the makings of an explosive scandal. At the same time, Lisbeth Salander is desperate to track down her old hacker friend, Plague, who has disappeared. When it becomes clear that both she and Svala are on a secret underworld hit list, Lisbeth decides to go to war with old and new enemies alike.