 EPA CID agent Jack Taggert is sent to investigate, after a fellow agent is found dead, probably not by accident.The EPA has received an anonymous letter from Jackson, Kentucky, and Taggert goes there undercover to continue his colleague's investigations.It is discovered that Hanner Coal Company, owned by Orin Hanner Sr., is being paid to dump toxic waste into an abandoned coal mine shaft, so Jack is assigned to go to the small town of Jackson, where his cover is that of assistant and volunteer carpenter to a local church.