A plague seems to be affecting a small English village at the turn of the century (Hammer loved recycling sets, actors, directors and plot ideas). Charles Spalding (David Baron) finds a note telling to go to Dr. Franklyn’s (Noel Willman) house. Charles arrives but finds no one home. He enters the house only to be attacked and bitten by something in the shadows. He dies with his face all blackened.
Charles’ brother Harry (Ray Barrett) inherits Charles’ place and moves in with his wife Valerie (Jennifer Daniel). Harry wants to know what killed his brother. He befriends local businessman Tom Bailey (Michael Ripper) and questions the local eccentric Mad Peter (John Laurie). Peter turns up dead with the same blackened face. Harry and Tom dig up the bodies of Peter and Charles and discover that both men died from a large snake bite.
Meanwhile Dr. Frankiyn’s daughter Anna (Jacqueline Pearce) invites the Spaldings to dinner where the good doctor displays some very hostile behavior toward his daughter. Harry later gets a note from Anna asking for help. When he goes, he is attacked by a humanoid reptile creature. Soon it becomes clear that someone is involved in a snake cult.
Borrowing a little from the 1955 Cult of the Cobra, Hammer tried to bring in a new monster instead the usual vampires and man made monstrosities that encompassed the screens. While the monster isn’t great looking, director John Gilling wisely choose to keep the beast hidden in shadows for most of the movie creating a nice uneasy menace. Shot on the same sets as The Plague of Zombies it was double-billed with Rasputin: The Mad Monk. While considered a B-movie effort from Hammer it still a pretty good movie which teaches us the useful lesson of not pissing off snake cults.