At the beginning of the Republic of China the remote town of Gulou in the North has been plagued by the mysterious disease - 'Skeleton Syndrome'. Patients suffer from speech and behavioral disorders, suffer from anorexia, and soon become living skeletons. In the town of Bones, a young girl Sanjian has been learning the art of hunting under her master, Sun Laohai, since she was young, and has developed an excellent archery skill. So the girl secretly vowed to hunt the notorious Black Beast for life as their mission, so often wandering in the nearby hazelnut forest to find the monster traces.