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David Lagercrantz continued the Millennium series after Stieg Larsson's untimely death in 2004. Lagercrantz, a Swedish journalist and author, was chosen by Larsson's estate to complete the unfinished fourth book in the series, "The Girl in the Spider's Web." Lagercrantz's continuation of the series has been met with mixed reviews, with some critics praising his ability to capture Larsson's style and others criticizing his departure from the original author's vision.