Karl Stig-Erland "Stieg" Larsson was a Swedish writer, journalist, and far-left activist. He is best known for writing the first trilogy in the Millennium series of crime novels, which was published posthumously, starting in 2005, after he died of a sudden heart attack. The trilogy was adapted as three motion pictures in Sweden, and one in the United States. Larsson had conceived of ten books in the series; the publisher commissioned David Lagercrantz to write the next trilogy, and Karin Smirnoff to write the third trilogy in the series, which has eight novels as of December 2025. For much of his life, Larsson lived and worked in Stockholm. His journalistic work covered socialist politics and he acted as an independent researcher of right-wing extremism.