In the melee, the pallbearers drop the casket over the side of a bridge, revealing the corpse of John Martinus, a recently deceased man.

As Sylvia departs the house, she encounters a grey-skinned man near an abandoned tin mine headframe, and watches in horror as he throws Alice's lifeless body onto the ground.

Police accuse Tom, the brother of John Martinus, of killing Alice, as he was found sleeping in a drunken stupor near her body.

An autopsy on Alice shows no signs of rigor mortis, and, even stranger, blood smeared on her face is determined to be of animal origin.

Through further investigation, Sir James and Peter learn that the squire lived in Haiti for several years and practised Haitian voodoo rituals, as well as black magic.

It is revealed that Squire Hamilton has been turning the locals into the walking dead, in order to create workers to mine the tin and make money off of it.

"[9] Time Out London wrote "perhaps a little tame these days, compared with modern gore-shock, but Gilling's Hammer chiller [...] is highly atmospheric.

A unique and shocking experiment in pushing the parameters of Hammer horror, The Plague of the Zombies deserves greater recognition in its own right.

[12] Radio Times gave the film four stars and called it "John Gilling's best work" It currently holds an 83% approval rating on Rotten Tomatoes, based on 12 reviews.

[15] The film was adapted into a 13-page comic strip for the October 1977 issue of the magazine House of Hammer (volume 1, # 13, published by Top Sellers Limited).