The novel delves into the corrupt practices within powerful families and corporations. The Vanger family's dark secrets and the unethical behavior of influential figures highlight the pervasive nature of corruption and its impact on individuals and society.

Lisbeth Salander's quest for justice and her personal vendettas drive much of the narrative. Her actions challenge traditional notions of justice, raising questions about morality and the lengths one should go to right wrongs.

Both Blomkvist and Salander experience isolation in different forms, yet their partnership becomes a source of strength and connection. The theme explores how relationships can provide support and empowerment, even in the face of adversity.