A virus is wreaking havoc in the world—one that’s transmitted by flies. Gigantic swarms of insects sweep everything away, devouring people and animals while infecting the survivors with a terrible disease. Infrastructure is destroyed; cities have turned into ruins. A few who survived are hiding in the deep woods. Among them is a scientist who endlessly tells his daughter Niko a legend about a mysterious geological anomaly discovered in Manchester—in the waters of the Merrimack River. When the scientist’s wife dies from the virus and he himself becomes gravely ill, Niko goes to Manchester with her faithful dog Harry. On the way, she meets other kids heading in the same direction. Each has their own story, but somehow all of them are intertwined in strange ways. The kids have only to put the found keys together—and a mysterious Deliverer, who lives one life after another in an attempt to steer events into the course he needs, helps them.