Crusading publisher Mikael Blomkvist has decided to run an explosive exposé of a wide-ranging sex trafficking operation. Just before piece is published, two people are brutally murdered. The fingerprints on the murder weapon belong to his friend, the troubled hacker genius Lisbeth Salander. Blomkvist, convinced of Salander's innocence, plunges into an investigation. Meanwhile, Lisbeth herself is drawn into a murderous game of cat and mouse, and is forced to face her dark past.