In the French costume drama The Last Mistress, appearances are deceiving. Raw looks have little to do with sexual potency.

There is a startling example here. In a flashback scene to their first meeting, the pouty-lipped hero played by Fu'ad Ait Aattou looks at the siren wench played by Asia Argento and calls her "an ugly mutt."

The Spanish courtesan defiantly and lasciviously licks her ice cream cone. He smiles. They promptly begin a tempestuous 10-year love affair. Throughout the decade, he remains prettier, even more feminine, than she ... by far. Yet the 'mutt' remains more potent than he ... by far.

This being a film by the enlightened Paris provocateur Catherine Breillat, gender politics are constantly in play. But not in her usual bold manner. Breillat, who usually makes contemporary movies loaded with explicit sexual scenes that even show penetration, steps back here in a restrained satire about love, infidelity, betrayal and the sordid affairs of the French gentry.

It plays in studied, high-born French with English subtitles. Writer-director Breillat adapted The Last Mistress from the novel by Jules-Amedee Barbey d'Aurevilly. The story is set in 1835 when Aattou, as a bankrupt young playboy is set to marry the virginal and rich daughter of an aristocratic family.

He still has Argento on the side and she is known to all Paris by this point. Still, he vows to give her up for the blond virgin played as a pretty object of desire (but no fire) by Roxane Mesquida. Why the moody, pleasure-seeking young man would fall in love with the dull if pretty doll is a mystery, because this love is supposed to be sincere and not just gold-digging.

In any case, the courtesan is not so easily discarded. Hell hath no fury and all that. Argento, as the ugly mutt, has a bite to go with her bark.

It is de rigeur for films critics to lionize the films of Breillat. Some truly are remarkable, such as the haunting tragedy Fat Girl, which managed to get banned for a year in some Canadian provinces because of its assault on our senses.

But The Last Mistress -- known as La Vieille Maitresse in French, implying a very different sensibility -- is not one of the great ones in her canon. It is merely interesting and easily disposable.

Not that the film is worthless. It is sumptuous, because Paris of that era is effectively recreated. It is amusing, because there are droll observations about society, especially from the grandmother so marvellously played by veteran actress Claude Sarraute. And it is free-willed, because Breillat does not hew to old traditions in relationships.

But it is also stagey and plodding. That makes it, ultimately, rather boring. And soon forgotten.

(This film is rated 18-A)

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