Swedish author David Lagercrantz, who took over the Millennium crime series from the late Stieg Larsson, made the remarkable announcement that the fifth book will be written in a new style: like Raymond Chandler or even Lagercrantz's own ghosted biography of footballer Zlatan Ibrahimovic.

Millennium is a collection of best-selling and award-winning crime novels that were intended to be a series of 10 by Larsson, who died suddenly in 2004 leaving only three books: The Girl with the Dragon Tattoo, The Girl Who Played With Fire and The Girl Who Kicked the Hornets' Nest.

A fourth book, The Girl in the Spider's Web, was based on Larsson's characters, especially the female protagonist Lisbeth Salander and was commissioned from author and crime journalist Lagercrantz by publishers Norstedts.