Sömngångaren by Lars Kepler

When a string of brutal killings rattles Stockholm, Inspector Joona Linna leads a tense investigation that blends forensic detail and psychological profiling; clues point to a perpetrator whose actions seem to stem from dissociation or sleepwalking, and as Linna peels back layers of deception, revenge and buried trauma he must confront unsettling links between past and present in a high-stakes cat-and-mouse pursuit.

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