The Manor House used for the exterior shots of the school appears as a hotel used for a clandestine assignation in The Rough & The Smooth (1959); as the tennis club in School For Scoundrels (1960); as Rod Taylor's training ground in The Liquidator (1965); as "The Elizabethan Hotel" in The Avengers episode Wish You Were Here [12/2/69]; as "Merston Manor" in Randall & Hopkirk (Deceased) episode The House On Haunted Hill [16/11/69] as residences in episodes 7 & 14 of the same series; and as the restaurant used by Strand and his companion in Special Branch S4 episode 12, Diversion.
This was the last of three films directed by Jimmy Sangster. The others were The Horror of Frankenstein (1970) and Lust for a Vampire (1971). Ralph Bates appeared in all three films.
After Taste the Blood of Dracula (1970), The Horror of Frankenstein (1970), Lust for a Vampire (1971) and Dr Jekyll & Sister Hyde (1971), this was Ralph Bates' fifth and final Hammer film.
Director Jimmy Sangster said Joan Collins was a little difficult to work with. She had been a star but her career was in a severe dip when she did this movie and she wasn't happy about it. It didn't rise again until she did the US TV show Dynasty (1981).
Co-stars Joan Collins and Peter Cushing had been castmates also in Tales from the Crypt (1972) released a few months earlier, but since they were in different stories in that film, they did not appear together on screen.