A gripping crime thriller by David Lagercrantz and the sixth and final novel in the modern Millennium series. It serves as the conclusion to Lagercrantz's continuation of the saga featuring hacker Lisbeth Salander and journalist Mikael Blomkvist.

After years of exposing corruption and confronting dangerous enemies, Lisbeth Salander is determined to settle unfinished business with her past—particularly with her estranged twin sister, Camilla Salander, whose ruthless ambition and psychological manipulation have haunted Lisbeth for years.

Meanwhile, Mikael Blomkvist is investigating the suspicious death of a homeless man who appears to have possessed critical information linking powerful politicians, criminal networks, and international intelligence operations. As Blomkvist follows the trail, he uncovers connections that lead directly to Lisbeth's personal history.

Their separate investigations gradually converge, revealing a far-reaching conspiracy involving organized crime, abuse of power, family betrayal, and long-buried secrets. Forced into a final confrontation with Camilla, Lisbeth must face both her greatest enemy and the emotional scars of her childhood. The novel combines cybercrime, espionage, murder, and psychological suspense while bringing closure to the conflicts introduced in the previous books.

Fast-paced and emotionally charged, The Girl Who Lived Twice delivers an action-packed finale that explores themes of revenge, identity, trauma, justice, and redemption.