Why are the villagers of a sleepy little town like Hartlewick disappearing? Has the archeological excavation of an ancient Druidic mound awakened something that was better left undisturbed? And are these strange occurrences related to the presence of a mysterious energy field?The Time Lord and his Companions are sent to Hartlewick, England to locate the source of this unexplained energy field. But they do not have much time. Forces are at work to unleash something hideous and all-too-powerful upon the residents of 1923 Earth.