This is not only the 3rd installment in the "Joona Linna Mystery" series by the married, Swedish, literary couple, Lars Kepler -- it just might be the best.
Joona Linna is Sweden's version of Sherlock Holmes. He's fiercely independent, caring, headstrong, "never wrong" and always gets his man (or woman). This was evident in their premier novel, The Hypnotist. These characteristics were further supported in the sequel, The Nightmare. Joona is not only a brilliant investigator, he is a formidable martial artist who's trim, tenacious, and tragic.
Almost 20 years ago, Joona sent his wife and young daughter away to protect them from evil-doers that were seeking revenge. Joona has had no contact with either and longs for his lost loves. He has a soft spot when children are involved in his investigations.
The Fire Witness is loaded with soft spots. A double-murder is committed at a home for wayward girls. The prime suspect, Vicki, only a child herself, flees the crime scene and while on the run, is suspected of kidnapping another younger child...a boy who is briefly left unattended in a parked car. It is not Joona's case, since he is on suspension for previous traitorous conduct. Joona is able to position himself as an "observer" where he proceeds to get emotionally involved in the hunt for Vicky.
Joona also proceeds to get into more trouble with his superiors by not following the conditions of his suspension. He enrolls the aid of a local "medium" who thinks she has seen the true killer. Her visions are discounted immediately by the unimaginative police investigators assigned to the homicide/kidnapping, but not by Joona, who never discounts anything.
There are a load of suspects that are not discounted by Joona. In between his continuing search for his wife and daughter and that of Vicky and the boy hostage, Joona juggles his schedule for his suspension hearing and his ongoing romance with a fellow policewoman.
Lars Kepler in reality is Alexander Ahndoril and his wife Alexandra Coelho Ahndoril. They create magic together and have a long, successful career in their future, and one doesn't have to be a seer to know that...just an avid mystery reader.