Stieg Larsson's first novel, The Girl with the Dragon Tattoo, was a publishing sensation. It took Sweden by storm and received rapturous reviews when it appeared in Britain last year. Larsson's own story (he delivered three novels and died suddenly soon after) is almost as extraordinary as the books. This second novel (translated by Reg Keeland) is even more gripping and astonishing than the first.

Again, the main characters are Mikael Blomkvist, a journalist on the radical magazine Millennium, and Lisbeth Salander, a computer hacker. In the first novel, they worked together on a case and had an affair, despite her solitary nature and apprehensions about men. Now she is avoiding Blomkvist for reasons he doesn't understand, but he is in any case distracted by an investigation into sex-trafficking in Sweden.

Almost 10 years ago, the Swedish government passed a law that criminalised buying sex. Against this background, Blomkvist is approached by a journalist, Svensson, with explosive information, including the claim that a civil servant who drafted the controversial law has been having sex with trafficked teenagers. Lawyers, cops and judges are involved, it's alleged.Blomkvist agrees to devote an issue of Millennium to the exposé, and Svensson starts making plans to confront the guilty men. Everyone knows it's a risky project, but nobody expects what follows: called to the flat where Svensson lives with his girlfriend, Blomkvist finds them both shot dead. While reeling from this shock, he receives another blow - Salander's fingerprints are on the gun. She becomes suspect number one and Blomkvist is in a desperate situation, grieving for his dead friends and unable to find her.

Salander is a much more solid character in this second outing, and the connection between her and the people responsible for trafficking girls is at the heart of its plot. Why she is so emotionally damaged emerges as she tries to discover who has framed her, relying on her computer skills and a band of reclusive hackers.

Conscious of the way crime and other networks transcend national boundaries, it's a very modern novel. What makes it outstanding is the author's ability to handle dozens of characters and parallel narratives without ever losing tension. Larsson was as vexed by misogyny as any author I've come across, but he was also a fantastic storyteller. This novel will leave readers on the edge of their seats.

The Girl Who Played with Fire by Stieg Larsson
translated by Reg Keeland
MacLehose Press £16.99 pp572

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