She holds a secret in her hands as she remembers his dying words, "you need to keep this safe!" A fire at a disused World War II bunker in Belltrees sets off a train of events that causes disturbance after disturbance in the small community, involving a myriad of characters, from dogs and children to the "subjects" of secret experiments. The locals in Belltrees feel under threat by the escapees from the bunker, and two of them are murdered...