Airdate: 6 December 1980
Starring: Peter McEnery, Georgina Hale, Emrys James
Guest Stars: Anthony Brown, Conrad Phillips
Screenplay by: Don Shaw
Directed by: Don Leaver
During an operation, Samuel Holt, a man who tried to drill into his own head, shouts out, “Leave my soul alone.” He dies during the operation, and it transpires later that the man was trying to relieve pressure on his brain after believing he had been invaded by an evil virus.
New mortician Edwyn Rord becomes obsessed with the number nine. Living with his domineering mother, he relates his fears to Stella, their lodger, while collecting the rent.
He tells her that evil people are out to get him because he is pure and innocent and that they wear dark glasses because evil people cannot stand the sunlight. He is sure they made him accidentally prick his finger at work on purpose so that the evil virus would infect him.
Later, he becomes convinced that it is not his work colleagues who are out to get him but his mother. He uses numerological techniques on Samuel Holt’s name, and it equals nine. He uses the same technique on his own name and it also gives the answer nine.
He goes to a church to see a man of the cloth and shares his thoughts. He tells him that he believes he has been infected with a special virus disguised to look like meningitis; the same disease that killed his father. When Edwyn sees that the numbers on the vicar’s hymn board are all multiples of nine, he flees from the church screaming.
The feeling that his mother is the root cause of the evil virus becomes stronger, as does the certainty that it was she who killed his father. He plunges a dagger many times into her stomach and kills her. Stella, who believes that Edwyn may be a meal ticket, helps him dispose of the body in a freezer.
He goes back to work and suffers a total mental breakdown. Two doctors diagnose paranoia. Is this just part of an evil conspiracy against Edwyn?
Edwyn is sitting in the work canteen. A colleague reads out an article about a virus. The closing scene sees Edwyn at work in the operating theatre. Edwyn waits for the nurse to leave and then locks himself in. He takes a surgical drill, lies down on the operating table, turns on the drill and moves it towards his head.