The Girl in the Spider's Web is the 4th novel in the Millennium series (the 1st 3 were written by Stieg Larsson). It uses the characters of hacker Lisbeth Salander and journalist Mikael Blomkvist. The book was written in secrecy by David Lagercrantz who worked on a computer that didn't have an internet connection. Larsson's estate is controlled by Larsson's brother and father who hired Lagercrantz. In the novel, Lisbeth Salander becomes entangled with the Spider Society which is run by Lisbeth's sister, Camilla, who has taken over the criminal operation run by the girls' father. Lagercrantz has gone on to write 2 more books in the series - The Girl Who Takes an Eye for an Eye (2017) and The Girl Who Lived Twice (2019).