Boneshaker

When Briar Wilkes' son sneaks off into the walled off section of Seattle to find evidence that his father was not responsible for the destruction of that part of the city, Briar must risk her own life to save him from the deadly gas inside that turns people into rotters (the living dead). Inside she encounters a cast of shady characters who seek to help her because of who her father was. But it's not going to be that easy. The fearsome Dr Minnerecht, who not only builds terrible weapons to combat the rotters but runs the drug trade in ‘sap', a derivative of the poisonous gas that engulfs that part of the city, also seeks her out. Is he saint or demon or perhaps just a shadow of a man she once knew?

An excellent story. It was really difficult to put this down. Well-developed characters inhabiting a believable setting of an alternate-history American West. Highly recommended for fans of all genres.