Cornwall, 1860: a village suffers from mysterious lethargy and numerous odd deaths, so resident doctor Peter Tompson (Brook Williams) sends for the aid of his old friend and former teacher, Sir James Forbes (Andre Morell). Accompanied by his daughter, Sylvia (Diane Clare), Sir James arrives in the afflicted village and immediately runs afoul of a band of fox-hunting blue-blood assholes who, in their zeal to run down their prey, accidentally knock over a coffin being borne by two men. Upon crashing to the ground, the casket opens and exposes the body of the recently-deceased body of one of the bearers, who is none too pleased at the disruption and takes it out on the new arrivals. Since setting up practice in town twelve months previous, one local has died per each month of Dr. Tompson's presence, and he is at a loss to explain what the cause could be. As the locals' mistrust of Tompson percolates, Sir James find lodgings with Dr. Tompson and his wife, Alice (Jacqueline Pearce), and during an after-dinner conversation with the doctor, it is stated that Tompson has not been allowed to perform autopsies on any of the dead, both due to the villagers' reluctance at the perceived desecration of their loved ones' corpses, and also by the decree of Squire Clive Hamilton (John Carson), whose word amounts to local law in the eyes of the villagers. Since they cannot legally obtain a corpse for their investigation, Sir James and Dr. Tompson take it upon themselves to illegally exhume the body that was so rudely exposed by the fox-hunters, but upon opening the grave, the coffin is found to be empty...
Meanwhile, Alice has been looking haggard and behaving strangely, as she has been targeted by Hamilton for diabolical, voodoo-fueled purposes. Following Alice as she leaves in the middle of the night, a crying and terrified Sylvia is abducted by the returning fox-hunters and subjected to the preamble of what is clearly about to become a gang rape, which is thwarted just in time by an irate Squire Hamilton. Though allowed to depart unharmed and with a (seemingly) sincere apology from the Squire, Sylvia threatens to report the assault to legitimate authorities, but Hamilton persuades her not to do so, citing his appreciation and promising that the would-be rapists will be punished. On her way back to the doctor's house, Sylvia encounters Alice, now quite dead, in the arms of the undead brother who was missing from his coffin.
The deceased Alice, carried by the undead.
Horrified and in shock, Sylvia makes it home and informs her father of what she has seen. Alice's body is retrieved and an autopsy finally takes place, which yields the discovery that a sample of blood taken from Alice is not human. The investigation leads Sir James and Dr. Tompson to a forgotten mine on the moors, and from there the true horror of what's been transpiring beings to become clear.
Oh, what the young lads bring back after studying abroad...
Unbeknownst to the general public, Hamilton is the head of a clandestine voodoo cabal comprised of himself and the fox-hunting rape gang, and the Squire has been utilizing his voodoo powers (which he learned during his studies abroad during previous years) to steal and revive the bodies of the dead to serve as slaves in the abandoned mine, which now yields tin that the Squire and his followers will maintain their wealth with. Thus, it's only a matter of time until the forces of goodness and medical science engage in final conflict with black arts cribbed from black people.
Tompson encounters the living dead.
To be fair, the cast does their best with what the script gave them to work with, but one cannot make a gourmet meal from a can of Spam and a box of saltines. It is with a heavy heart that I rate THE PLAGUE OF ZOMBIES near the bottom of my estimation of Hammer's horror catalog. Perhaps not the worst they had to offer, but definitely a dull, tepid disappointment that does not warrant subsequent viewings.
Poster from the U.K. release.
Poster from the American release.