The Hypnotist by Lars Kepler
Lars Kepler is Swedish, and he's being billed, naturally, as the successor to Stieg Larsson. But Kepler casts a subtler, creepier spell than his countryman (Kepler is actually the pseudonym for a Swedish husband-and-wife writing team). The book starts with a bloodbath: Erik Maria Bark, an emphatically retired hypnotherapist, is called in to delve into the psyche of a young boy, the last survivor of a brutal killing spree who is incapacitated by shock. What comes forth from the depths of the boy's mind should be the end of the story, the solution to the crime, but instead it turns out to be only the beginning of a terrible chain of events that leads backward and forward in time. Kepler has a remarkable feeling for physical cruelty, and his ability to inhabit the workings of psychotic psyches is authentically shocking. Larsson is destined to have many heirs, but of this year's crop, Kepler is by far the best.