Based on the novel The Disorientated Man by Peter Saxon*, this Amicus film boasts the best line-up potentially ever in a horror film, with Christopher Lee, Peter Cushing and Vincent Price all appearing.
It starts with a man jogging, collapsing and waking up in a hospital missing his leg. He screams and then the same scream repeats as he loses every appendage. There’s also an Eastern European spy named Konratz (Marshall Jones, Cry of the Banshee) killing his superiors, including Cushing. Also times two, someone is killing young women in London and it looks like Keith (Michael Gothard) — a blood-drinking super-strong weirdo — is the murderer.
Price shows up as the sinister Dr. Browning and it all ends up being a conspiracy movie that owes a fair deal to Invasion of the Body Snatchers, but that movie didn’t end with much of its cast falling into acid.
According to Lee, the villains of this movie were going to be revealed as aliens, but that was cut out of the movie for some reason, leaving a lot of the movie unexplained.
There’s only one other movie to team Price, Lee and Cushing: House of the Long Shadows. They barely appear in any scenes together. though.
*A house pen name for multiple authors at Amalgamated Press; the Saxon that wrote this story is Stephen Frances edited by W. Howard Baker.