In December 2013, the Swedish publisher of the Millennium series, Norstedts Förlag, announced plans for a fourth Millennium book, written by David Lagercrantz, to be published in August 2015.[2][3] Extreme caution was taken to make sure details did not leak, and no early review copies were given out. Lagercrantz wrote the book on a computer that had no internet connection, and he personally handed his manuscripts to his publisher.[4] Lagercrantz reported the draft finished in January 2015.