Abandon hope all ye who enter here. Provocative French filmmaker Catherine Breillat returns with her traditional blend of controversy and explicitness – yet while A ma soeur! (2001) and Romance (1999) were compelling, if violent and troublesome, examinations of female sexuality, Anatomy of Hell is a study of blandly incessant sexual mores.

When a nameless man (Siffredi) prevents a nameless woman (Casar) from committing suicide, she pays him to visit her at her deserted house and watch her "where she’s unwatchable." For the next four nights, he seeks to learn the real secrets of how men see women, and how women see themselves. As far as a plot goes, that’s all there is – a never-ending huis clos of almost unwatchable bodily activity and discovery. It is a film obsessed with fluids and orifices – the film’s money shot, so to speak, revolves around an extended scene in which Siffredi inserts a pick-axe handle into Casar’s vagina, and then retires to a chair, pours a glass of whisky and stares loving at his latest piece of work.

And so the film really is an ‘anatomy of hell’ – an enclosed, claustrophobic room in which conversation and mutual respect end, and raw, visceral responses dominate. He is homosexual, and claims to have no interest in her sexually. Instead, his voyeurism is motivated by curiosity, which gradually moves to disgust, eroticism and finally, something close to admiration. Yet Siffredi’s blank face and eerie voice soon become tiresome – as an Italian adult film star, his approach to the film’s no-holds-barred sexuality is stoically professional, but his attempts at emoting are woefully short of the mark. Casar fares little better in a role that demands various stages of undress, but little else.

Now, perhaps there is a case to be made – as Breillat undoubtedly has – that the unnamed man and woman somehow represent the physical embodiments of attitudes towards the other sex. For example, the man’s comment, on seeing the woman lying naked on the bed, is that a woman’s "fragility" arouses either "homage or brutality" in the male. She counters this with the remark that men want "to lock up" women. These are important debates, but the film never really tackles in them in such a way to make them accessible or understandable.

This is a certainly not a ‘porn film’, as Breillat declares forcefully in the DVD’s accompanying interview. So what it this all about? A deliberately provocative attempt to make us think about modern sexuality and power relations? Perhaps a rigorous exploration of mutual gender hating? Neither of the characters has an identity, so perhaps the ‘him’ and ‘her’ then are ciphers, but for whom? She lives on a house on the edge of a cliff, an obvious symbol for otherworldliness or dreaminess, but again, answers remain frustratingly elusive.

Breillat’s pared-down aesthetic is again prominent – static camera, minimal editing, gestural performance – but it is a gruelling experience attempting to empathise with two characters wallowing in self-loathing. Eventually, it all becomes excessively monotonous.

Breillat argues in her interview that the film is about what constitutes obscenity, and that "our consciousness remains hidden, and we can never look things straight on." The director is to be congratulated, then, for tackling taboo and ‘difficult subjects’ but there is a danger now that she is becoming a one-trick pony, intent merely to recycle wilder variations of sexuality and submissiveness. Her next project, an adaptation of a Balzac novella, should herald a change of priority….shouldn’t it?