Thirty workers from the Shell refinery participated in the riot scenes filmed for The Frenzy (1955).
Monica Grey's character, Paula Quatermass, was merged with another character, an unnamed technician, shortly before the broadcast, which resulted in her character often talking to herself and answering her own questions.
Several episodes were preceded by a warning that the BBC considered it "unsuitable for children, or people with a nervous disposition."
Special effects crewmen Bernard Wilkie and Jack Kine make an appearance in The Destroyers (1955) as technicians assisting Professor Quatermass with his spacesuit. This was because the rubber spacesuit costume John Robinson wore was so heavy it prevented him from reaching his mark for the next scene, so he had to be carried across the studio.
Writer Nigel Kneale could not think of a dramatic title for the story, so he simply named it "Quatermass II" and justified it to himself by giving the same name to the nuclear-powered rocket which features centrally in the story.