The opening credits sequence of “A Girl Cut in Two” features a through-the-windshield view of a twisting road outside Lyon, France, and is drenched in the rich sounds of a Puccini aria and a suggestive shade of red. This is a Claude Chabrol film, however, and all this preliminary spilling of emotion is a Claude Chabrol joke. The punch line arrives when the driver shuts the music off with the flip of a switch.

Anyone familiar with the formidable oeuvre of this feather-fingered ironist, now 78, will see it coming. The love-triangle intrigue that lies ahead will have none of the throb or pomp of an opera. It will be executed with the lightness and efficiency of a well-organized parlor game.

Inspired by a headline-grabbing scandal from the early 20th century — to give away more would risk spoiling the climax — the story, written by Mr. Chabrol and Cécile Maistre, unfolds a bit awkwardly in present-day France, and its regular flashes of wit and only-in-France charm aren’t enough to overcome the fact that there’s no one in the film really worth caring about.

Gabrielle Deneige (Ludivine Sagnier) is a bright and attractive TV weather girl whose life changes the day a successful author named Charles Saint-Denis (François Berléand) comes to the station to be interviewed. He’s married and several decades older than Gabrielle, and she isn’t a big reader. There doesn’t seem to be much there. But there are still places where an aging man of letters can, with the right bon mot, dedicate a book to a nubile female and have her in the palm of his hand. Lyon is apparently one of them.

Charles treats the liaison casually; Gabrielle doesn’t. Eventually, his rude treatment of her — including a lurid sexual initiation that is administered on her birthday at his private club and left tantalizingly unexplained — drives her into the arms (or at least the plush convertible) of an insufferable brat named Paul (Benoît Magimel), who has been pining after her for some time.

Paul, the son in a prominent local family, is an ardent young suitor — and an enormous turnoff as a character. There’s an amusing running joke that has him tossing things that displease him over his shoulder, such as a parking ticket. But he doesn’t have a charming insouciance. He’s desperate and depraved, and his persistent come-ons to Gabrielle range between insincere and menacing. Mr. Magimel, in an overly theatrical turn, plays Paul as a snarling queen.

Paul is too showy and simpering to take seriously but, before long, the film is asking the audience to do just that. There’s something genuine, it turns out, behind his smarmy overtures, and Gabrielle begins to show interest. Mostly, she wants to get back at Charles, but she misjudges what she’s up against. Most directors would make the film about her, but Mr. Chabrol seems more drawn to Charles, the self-satisfied intellectual who likes to hang out with sexual dilettantes and quote famous poets. He also has a clear fascination with Charles’s icy, dominant mother (Caroline Sihol).

Mr. Chabrol’s direction, for better or worse, seems as effortless as ever. Some scenes feel incomplete but, oddly, the sharper for it. On the other hand, there’s a strong whiff of indifference hanging around this tale of privileged seducers and their corrosive ways.

Only in a rarefied little world would Ms. Sagnier, who deserved all the acclaim she received for the insolent sexpot she played in François Ozon’s “Swimming Pool,” be stuck between two men as unsatisfactory as Paul and Charles. Mr. Chabrol, no rube, repeatedly tips his hat to the artifice of it all: a shot of Gabrielle in front of a green screen; Paul chucking Charles’s book at the camera; Charles entering a scene through a fitting-room curtain. The climactic act takes place on a dais, in front of a large audience, and the epilogue has Gabrielle, now moonlighting as a magician’s assistant, being sawn in half on a stage.

But Mr. Chabrol, for all his cleverness and proficiency, is merely snipping a rope that is slack to begin with. To have viewers recognize his film as contrivance and yet also attach themselves to it — now that would be a neat trick.