Wissenswertes

The film is considered to be the earliest Spanish horror film.

First installment of the saga that would continue 'Dr. Orloff's Monster' (1964), 'Orloff Against the Invisible Man' (1970) and 'Revenge in the House of Usher' (1983).

Howard Vernon continued to appear in a number of Franco's horror films up until his death In 1996.

While filming his tribute to Hollywood musical films (Vampiresas 1930), director Jesús Franco convinced his producers to watch the British film The Brides of Dracula (1960). After the screening, Franco proposed that he could make similar films "in the same vein, but with a different style". Franco eventually convinced the same French co-producer who produced Vampiresas 1930.

Franco was concerned how the film would be handled by Spanish censors. As a result, he produced two versions of the film, one that was unedited and one that was for British and Spanish audiences that had the scenes with nudity in them cut. Spanish censors were also concerned with films that would damage the reputation of Spain. To avoid this, Franco set the film in France, a scheme that would later be employed by other Spanish horror filmmakers like Paul Naschy.

Jesús Franco: Man playing piano in bar.