Yann Gonzalez is the French director who startled UK audiences with his last film in 2013, an eroto-surrealist extravaganza called You and the Night, starring Eric Cantona as a legendarily endowed stud who exists in an eternal twilight of vampire priapism.

If that were not enough, he has now come to the Cannes competition and detained us all for an hour and 40 minutes with a bizarre new piece of fantasy: a weird mix of hardcore whimsy-porn that pays pert, tongue-in-cheek homage to what might be seen as the quainter and even more innocent days of 70s gay erotica, but with a harsher, darker streak of violence.

It seems to have something of Bertrand Bonello’s The Pornographer and also that locus classicus of high-art porn - Walerian Borowczyk’s 1975 film The Beast. There is an almost homeopathically small touch of Almodóvar and also a cheeky steal from John Landis’s An American Werewolf in London.

It really is strange, a film with what is actually a pretty good premise for a comedy, but with no interest in actually being a comedy and also no interest in being a thriller, or even that mysterious erotic parable that it seems to be claiming to be. It isn’t funny enough – or serious enough. But I concede that it might acquire a cult midnight-movie status.

Vanessa Paradis plays Anne Pareze, the proprietor of a film production company in late-70s Paris, churning out cheapo gay porn for an enthusiastic clientele. Anne is still passionately in love with Lois (Kate Moran) who edits the firm’s films - and Anne refuses to accept that their relationship is over. She is always drunk-dialling Lois late at night.

And to add to this heartache, there is horror. A serial killer, who wears a horrible “leatherface” mask and cruises gay nightclubs, is picking up the guys who act in Anne’s films and killing them with a blade that snaps out of his dildo. The police have no great interest in helping gay men in trouble, but their callousness provides Anne with a grotesque new artistic inspiration. She will make a gay porn film version of the case, as it unfolds, with her experiences of the investigation transformed into bad-acting porn. The title is Le Tueur Homo, subtitled here as Homocidal. It could be her masterpiece.

There is something brilliant about it, but Gonzalez doesn’t dwell on that gag, as such. We veer off in a weird new direction as one of the (real) cops gives Anne a crime-scene clue – a black bird’s feather. Anne succeeds in finding a bird expert in the phone book (no Google in those days) – a man with a claw for a hand. Of course! He says that this bird comes from a semi-fabular breed of blind bird that lives in a remote forest. Anne naturally shows up there, looking for clues in the company of a local woman – a cameo by Romane Bohringer – and she discovers a young man’s grave. The deceased’s identity will give her the truth about the murderer and his fateful connection with Anne and her inspirational oeuvre.

It’s a film that exists in the tatty, seedy, red-lit porn world of adult movie theatres and clubs. Gonzalez has a feel for the exoticism and occult lure and lore of this world. But it is trying very hard for something more, some enigma that exists above and beyond it all. And by the end of the film, there is nothing more – just the tail wag on a shaggy-dog story of cheesy erotica.