Mikael Blomkvist, a journalist, and Lisbeth Salander, a troubled and enigmatic computer hacker. The plot revolves around a decades-old disappearance case of Harriet Vanger, a member of the powerful Vanger family.
Mikael Blomkvist, after losing a libel case against a wealthy businessman, is hired by Henrik Vanger, an elderly industrialist, to solve the mystery of Harriet's disappearance. Blomkvist moves to the Vanger family's remote island and starts investigating the case. As he delves deeper into Harriet's vanishing, he discovers a series of dark family secrets, including a history of violence and abuse within the Vanger dynasty.
Meanwhile, Lisbeth Salander, a brilliant but socially withdrawn young woman, crosses paths with Blomkvist. She possesses exceptional computer hacking skills, which she uses to gather information and carry out personal vendettas against abusive individuals. Salander becomes involved in Blomkvist's investigation, and together they uncover a sinister web of corruption, misogyny, and murder.
As the story progresses, Blomkvist and Salander encounter numerous obstacles and dangerous individuals who try to stop them from uncovering the truth. The narrative explores themes of misogyny, sexual violence, corporate corruption, and the abuse of power. Both characters face personal demons and confront their traumatic pasts while navigating a treacherous world of deceit and betrayal.