A wave of films with explicitly sexual themes is sweeping through the Cannes Croisette this year but not all the entries are necessarily plain sleazy.

American director John Cameron Mitchell's "Shortbus", a small $2 million flick that was screened Out of Competition in a post-midnight slot, goes further into graphic sex territory than any film ever has without sinking into the morass of pornography.

The film is about an underground New York salon where people meet to indulge in or watch other people indulge in an array of sexual activity as a defence mechanism against their fears, frustrations and failings.

"Red Road", an In Competition British film directed by Andrea Arnold, who won last year's Oscar in the best short film category for "Wasp", climaxes with protracted and authentic cunnilingus, without anybody batting an eyelid. It would seem Cannes regulars have become inured to such on-screen display of skin even as they are fully aware that sex sells.

In the Directors' Fortnight this year, there is Jean-Claude Brisseau's "Exterminating Angel", a film that presents a no-holds barred exploration of the casting couch syndrome. Interestingly, Brisseau himself was once accused of exploiting his actresses.

In other sidebar sections of the 59th Cannes Film Festival are such films as "Destricted", a documentary that strings together a series of erotic short films helmed by directors who have spent a large part of their careers defying norms and pushing the boundaries.

For all the skin that is on show, "Destricted" is essentially an art house film that showcases various ways in which art meets sexuality.

In the Un Certain Regard line-up is "Taxidermia", an avant-garde film by Hungarian director Gyorgy Palfi, which offers a sometimes laboured, sometimes funny cocktail of sex, gluttony and immolation.

Cannes has of course never been known to shy away from sexually explosive material. Last year, one of the films in competition was Carlos Reygadas' Mexican entry, "Battle in Heaven", which opened with one of the longest oral sex sequences ever seen in a mainstream film.

In 2004, Cannes presented festival goers with British director Michael Winterbottom's "9 Songs", which blended music and graphic sex in a manner no film has ever done.

In 2003, Cannes had American actor-composer-director Vincent Gallo's "Brown Bunny" in the official selection. Its graphic fellatio sequence became the talking point of the festival even as the director was hauled over the coals by a section of critics.

In 2001, French filmmaker Claire Denis contributed her mite to Cannes' substantial sex and sleaze folklore with "Trouble Ever Day". The film, starring Vincent Gallo, linked cannibalism with sex, a fact announced unabashedly in one of its publicity taglines: "I love so much, I can eat you."

A year earlier, Argentine director Gaspar Noe, who has a film in the "Destricted" collection, had earned ill fame with "Irreversible", which featured a prolonged, particularly nasty, rape scene.

The saga continues...and it seems irreversible.