Grade: C-

It takes about twenty minutes to tire of the characters in the ironically-titled “Happily Ever Afrer,” a sour, grating comedy-drama about fidelity and infidelity among the Parisian bourgeoisie from writer-director-star Yvan Attal. There are plenty of adults wandering about in the multi-tasking auteur’s story of love and lust involving two married couples and their bachelor friend, but the only person in the piece who’s remotely engaging–apart from the moonlighting Johnny Depp, who shows up for a cameo–is the young son of one of the couples. And he’s not around nearly enough.

The chief focus is on Vincent (Attal), a car salesman, and his wife, realtor Gabriele (Charlotte Gainsbourg); they’re the ones with the precocious tyke, Joseph (Ben Attal, the son of Attal and Gainsbourg in real life). Vincent and Gabriele are an apparently content, loving pair, but he’s actually got a mistress on the side–a masseuse (Angie David)–and is considering leaving Gabriele for her, while she fantasizes about a young man (Depp) she bumps into in a music store. Meanwhile the marriage of Vincent’s close friend Georges (Alain Chabat), a hotelier, is, on the surface, much rockier. He and his wife Nathalie (Emmanuelle Seigner), a peevish woman who constantly berates him from a feminist perspective, spend virtually every waking moment shouting at one another; but Georges is nonetheless faithful to her (and she, presumably, to him). Contrasted to both Vincent and Georges is their pal Fred (Alain Cohen), the former’s co-worker, an unmarried Lothario whose constant conquests make them both envious (and for whom Georges regularly supplies the necessary rooms gratis). But, as becomes clear, Fred actually pines for the sort of married stability his friends possess but don’t sufficiently appreciate.

There’s certainly nothing wrong with a serio-comic look at adultery and the difficulty of holding to marriage vows, but the stridency of both Attal’s script and most of the performances in “Happily Ever After” pretty much obviate any charm or insight it might have possessed. A few examples may suffice to show how the film goes wrong. One of Vincent’s habits is to surprise his wife by literally jumping in on her unawares, especially when she’s bathing Joseph so that the kid’s fright will end in her being soaked. Maybe this peculiarity is intended as a kind of sign that Vincent’s attempting to infuse some much-needed excitement into his marriage (like the couple’s apparent predilection for role-playing when out on the town, as in the affected first sequence), but in fact it just makes him seem like an inconsiderate jerk. (You can understand why his mistress reacts so angrily when he tries it on her by splashing her with water.) As if that weren’t bad enough, on one occasion the practice leads to a drawn-out chase in their apartment, in the course of which the duo not only douse each other with water but with all sorts of food as well, both winding up covered with gook before they tumble into bed for some heavy sex. (And the whole protracted, noisy incident is supposed to occur just after Joseph has been put to bed with his door ajar, but it doesn’t disturb him in the slightest.) This episode is presumably supposed to have the same effect the famous eating scene in Tony Richardson’s “Tom Jones” did–to show the build-up of desire before the final explosion, as it were–but it comes across as kind of nauseating rather than engagingly sloppy. Then there’s the matter of a major coincidence that’s built into the plot. One evening Gabriele and the other woman accidentally find themselves seated beside one another in a restaurant. That alone strains credulity when one considers the size of the city they’re living in, but there’s more: the mistress, talking to her mother about her affair with Vincent, overhears Gabriele telling the friend she’s dining with that she suspects her husband of infidelity. Then Gabriele conveniently drops her purse, and just happens to leave behind not only a photo of her and Vincent that the other woman can pick up to confirm the identification, but her cell phone, which Vincent calls on just in time for his mistress to answer and hear his voice. Sure. And then, at the end, who do you think turns out to be the person to whom Gabriele has to show a ritzy apartment? No need to say–you already know. Or is it merely a daydream? Who cares?

And that’s the fundamental problem with “Happily Ever After”–it’s impossible to give a whit about any of these self-absorbed, perpetually unsatisfied people and their constant stream of witless whining about the problems in their lives. Perhaps if they were better acted one might feel differently, but Attal is bland, Gainsbourg beautiful but blank, Chebat irritatingly loud and Seigner obnoxious until she turns unaccountably nice at the end. Meanwhile Cohen, a non-professional who as a child starred in producer Claude Berri’s “The Two of Us” (1968), shouldn’t jettison his day job, and David looks understandably glum for the most part. But Berri and Anouk Aimee provide a few nice moments as Vincent’s parents, him looking a bit dilapidated and her appropriately long-suffering. Still, it’s little Ben Attal who comes off best–a delightfully rambunctious tyke, much more natural than his parents–and Depp at least proves himself a good sport in his walk-on. The picture doesn’t even show off Paris to best advantage; Remy Chevrin’s cinematography, however, does improve in the few rustic scenes toward the close, and gives a radiant glow to the final sequence.

But whatever the title implies, this movie certainly won’t send you home with a smile on your face.