Having helped fend off the attack the spirit riders now have access to the city. They do set people's nerves on edge however. Nolan meanwhile has a murder to solve after they find the remains of Dalton Taggart in the nearby woods. There's not much left of him but after a second citizen. Boyd Bowen, is butchered Nolan believes he was attacked by a particularly vicious creature known as hellbugs. After a second attack on Datak Tarr and his family, Nolan concludes that pheromones are being used to target people. He now not only has to find the hellbugs' nest but also the person using them as a weapon. Irisa's special abilities prove to be particularly useful.