Beware the man-beast when the moon is full, for it unleashes the terror and violence known as...The Hyde Effect!
In the hills of Southern California, a series of violent and gruesome deaths occurs within the space of a few hours. The murders are attributed to some unknown, savage animal.
Precisely one month later, college student Meg Talley is attacked in the same manner. Astonishingly, she survives, but when she insists that her assailant was a hideous monster-like creature, she is called hysterical.
Journalist Douglas Morgan, private eye Nick Grundel, and horror novelist Blake Corbett, however, have each theorized that the mangling, incredible though it seems, might be the work of a werewolf. Now they team up with Meg to pursue an intensive investigation. When a suspect is apprehended and confined, the four are on hand. But neither skeptics nor believers are prepared for the bone-chilling terror and cataclysmic violence that will be unleashed in the night of the January full moon.