Sure, this delicious new Merchant-Ivory production makes fun of the French, just a bit, in that traditional, time-honored way of They're French, what can you do? "Everything is worse when the French are involved," sniffs Stephen Fry's British art appraiser, but it's with a kind of affection that he does so. Le Divorce is about making fun of everyone, just a bit, about recognizing and celebrating cultural differences as the things that makes us appealing and interesting and, okay, yes, frustrating, to one another on an international scale. You better believe that the French make fun of us Americans, too -- on the screen here as well as in reality -- with exactly as much justification as we Americans have in reverse, which is to say none at all and all we need.

It's mostly all about sex, too, is Le Divorce, and the various ways in which Americans and the French are obsessed with it and go about having it, the Yanks so blunt and earthy, the French with their precise rules about how to leave your wife and how to acquire a mistress. Not to mislead: This is a grownup movie about sex, all in your head and not on the screen, a comedy of manners in which even talk itself about sex is pretty circumspect. Unlikely as it may seem at first, this very contemporary film about very contemporary mores and behavior fits perfectly into the Merchant-Ivory oeuvre populated by the demurely passionate historical people of Remains of the Day and Howards End and A Room with a View. And we think we're so modern. Plus ça change, and all that.

Kate Hudson, who can be so infuriatingly grating in films that demand she be both sexy and childlike at the same time -- see Alex and Emma or How to Lose a Guy in 10 Days -- is wonderful here, as the American Isabel who, under the influence of Paris, transforms from a golden California girl, all gypsy blouses and bubbly sunshine, into a sophisticated Frenchwoman, in smart suits and stylish scarves, though she has some issues with handbags that shock the natives and she's still American enough to dismiss the reaction with a laugh. She's embracing the French idea of morality -- becoming the mistress of the married Uncle Edgar (the austere Thierry Lhermitte), who's not, never fear, a blood relative -- just as her sister, ex-pat Roxy, is commencing her own one-woman battle with the ideas the French have with regards to fidelity.

Naomi Watts (The Ring, Mulholland Drive), who is never infuriating or grating, is an excellent foil to Hudson, her Roxy retaining her earthy Americanness even as she refuses to give up the Frenchness she's acquired living in Paris, being married to Charles-Henri (the appropriately weaselly Melvil Poupaud), raising their young daughter, and now carrying their second child. Charles-Henri moves out, wants a divorce, another aspect of love and sex and relationships for which the French have definite rules and expectations and family entanglements that don't sit well with American sensibilities, particularly Californian ones. So Roxy asserts her Americanness, and grits her teeth and digs in her heels when the French are shocked by her.

Le Divorce meanders, loses its way a few times, and loses its tone a bit too much toward the end to be entirely forgiven -- the novel, by Diane Johnson, probably handled these things better, as is usually the case -- but there's far too much that yummy and sharp and canny to let this one get away. If nothing else, it's never a bad thing to see so many worshippable actors -- Stockard Channing, Sam Waterston, Bebe Neuwirth, Glenn Close, the aforementioned Fry -- have the chance to be onscreen the smart, funny people we suspect they are in real life. And it's far too rare that we get the chance to be a smart, sophisticated audience to pass up this opportunity to revel in a film that speaks to us as equals.