The Fire Witness (Joona Linna #3 - Lars Kepler

Flora Hansen calls herself a medium and makes a living by pretending to commune with the dead. But after a gruesome murder at a rural home for wayward girls, Hansen begins to suffer visions that are all too real. She calls the police, claiming to have seen a ghost, but only one detective puts aside his skepticism long enough to listen: Joona Linna.