Two versions were released: an R-rated and an uncensored hardcore version with explicit sex scenes. The hardcore version wasn't legal in Spain where it was made, so it was distributed in countries where it was allowed. Some if the actors who participated in the hardcore sex scenes signed contracts assuring them that version would never make it to Spain where it may harm their careers. Lina Romay didn't care where it was shown. She was an unabashed exhibitionist and enjoyed performing nude and having sex while people watched. Director Carlos Aured said he filmed the sex scenes with the help of a professional hardcore actor. At that time, there were not that many non-porn male performers in Spain who could sustain the effort because they'd falter once the cameras started rolling.
Loosely based on the 1970s case of kidnapped heiress Patricia Heart.
The Italian version has many differences in relation to its Spanish counterpart. There is sort of an ironical voice-over in the Italian one. The Spanish version is dead serious at the beginning, when a voice-over claims that the story about to be told is entirely true and has invited comparisons with the Manson affair. At the end, a legend and voice-over gives us some spiel about what is so wrong with our society that it can produce such monsters.