Linda Vargas (Montserrat Prous) works a showgirl number with Maria Toledano (Kali Hansa, The Night of the Sorcerers) before picking up Ortiz (Manuel Pereiro),seducing him, calling the cops and killing herself by slicing her own throat, which implicates him in her murder.

His wife, Rosa (Jacqueline Laurent) attempts to learn the truth and discovers from Countess Anna de Monterey (Anne Libert, The Demons, A Virgin Among the Living Dead) that her husband assaulted Linda when she was just a young girl, going from drugs to, well, the title is Sinner: The Secret Diary of a Nymphomaniac, so you can guess the rest.

Made after the death of Soledad Miranda and before Franco would fall for Lina Romay, this comes from the more serious side of Jess Franco, feeling like it was inspired by the structure of Citizen Kane, which makes sense more than the absolutely formless movies he'd make later in his career.

The worst thing is that Jacqueline Laurent was fired from her position as a drama teacher at a private high school because of this film. Her students learned that she had appeared nude in this film - made 39 years before - and the school's administration claimed that this and other erotic thrillers made in the sixties and seventies posed a distraction.

Let's not mess about: a Jess Franco film concerning the titular 'Diary of a Nymphomaniac' is surely, purely an exercise in sleaze/eurotika/sexploitation cinema (take your pick). An excuse to show scenes of a young attractive woman (Linda, played by stunning Montserrat Prouse) trying to satiate her infinite appetite for sex.

Well, of course it is. But that's only part of the story. Filmed just after the death of Franco's muse Soledad Miranda (for whom the character Countess Anna de Monterey might have been written - here, the wonderful Anne Libert, an underrated Franco veteran, is given the role),there's a true air of melancholy about this. Subject to a series of sexual advances after running away from home (from another undisclosed trauma),she is far from the sexually confident, free spirited heroine we often meet in Franco's films. Her innocence is communicated to us in a heavy-handed, unsubtle way, but it convinces us enough to firmly find ourselves on her side. Meeting with the far more worldly-wise Anna, Linda slowly 'blossomed into a beautiful and sensuous young woman.' In other words, a bi-sexual nymphomaniac.

But her condition isn't used greatly as an excuse for gratuity. In fact, by Franco's standards, 'Sinner' is even somewhat restrained. Linda is a forlorn, moody figure, drug-addled and friendless. A victim of circumstances. I won't pretend this is a sensitive exploration into the psyche of an abuse victim, but it is nevertheless an interesting, seedy tale told with compassion.

Alongside Libert and Prouse, is Jacqueline Laurent who also features as an unappreciated wife in Franco's 'Lorna, The Exorcist' from the same year. Franco himself appears in a cameo as an uncredited Inspector Hernandez.

It is always good to see regular Howard Vernon. He isn't perhaps ideal to play a character sympathetic to Linda's plight, but here he plays an unnamed Doctor who vows to help the girl. Virtuously, he resists her natural advances and allows her to spend time at his hospital retreat. One night, he sees her liaison with a group of men and sees her as he feels she really is - a prostitute. As such, his bills are paid in kind and he rapes her. Linda's disconnection with the sex act is a mechanical acceptance. Interesting, just as his faith in her is broken, so she dismisses him as being 'just like the rest.'

Another essential character is provided by the music, here provided by Vladimir Cosma and Jean-Bernard Raiteux , which is excellent throughout. Tropical, haunting, heart-breaking and wistful, I wish it was a more widely available commercial release, not limited to an extra disc on the blu-ray.

What a let down. For a film about a nymphomaniac this was the most boring waste of 86 minutes I've ever seen. What little nudity there was, was poorly shot and sleazeless. Any time anything started to happen, cut and onto the next boring scene. This film screamed out for more, promised lots, and delivered very little. Sorry Jess, love some of your stuff but you scored an own goal with this one I'm afraid