Rumors abound about a missing scene in which Fran and Miriam are seen inside the caravan of John and Harriet. This rumor is borne out by production stills and a vague recollection by producer Brian Smedley-Aston that it was, indeed, shot.
The screenplay is credited to Diana Daubeney, director José Ramón Larraz's wife Diana. According to Larraz and producer Brian Smedley-Aston, she didn't actually write a word of it. She was credited because, as a British citizen, she filled a UK production quota.
What are the differences between the Anchor Bay DVD and the Blue Underground DVD?
When the Anchor Bay DVD was released, the fans were joyful - the DVD was advertised as being uncut & uncensored for the first time. 3 years later, Blue Underground re-released the movie - and made clear that the Anchor Bay version was (marginally) cut. Approx. 30 seconds are missing in the Anchor Bay Version. A detailed comparison between both versions with pictures can be found here.