This film was known as "The Wreckers" throughout filming, but the title was later changed.
Bernard Lee broke his arm after falling off a horse whilst drunk during the Welsh location filming, and had to stay overnight in a local hospital.
During location filming in South Wales, the film-makers were obliged to disguise telegraph poles as palm trees (which are rare in Britain).
Due to an oversight by the National Screen Service, none of the eight stills that were issued in the UK as part of this film's Front-of-House set contained an image of the film's star, Peter Cushing.
Shot June 20-July 1960, copyright 1960.