Long-undisturbed Tenebrion Wood, identified in the Domesday Book and named by the Romans after a kind of "night-sprit," stands in the way of a road development. Environmentalist Steve Pearlman recruits a number of investigators to examine the site in order to find some justification for its defense, including entomologist John Hazard. At first, the wood does not seem to be of any special scientific interest, despite the occasional profusion of its beetle population, but Hazard makes a surprising discovery in the clearing in the middle of the wood that changes the nature of his investigation drastically — and suggests that the wood's "night-spirits" might be something far stranger than mere ghosts or goblins...