Droll French comedy puts socialite-turned-awful-singer center stage

Starring Catherine Frot, Andre Marcon and Christa Theret. Directed by Xavier Giannoli.

Rated R for brief graphic nudity, sexual content and drug use. In French with English subtitles. Check listings for theaters. 2 hours, 7 minutes.

Bottom line: A dry, high comedy that achieves perfect pitch

If only love were all! Then loving what you live for — for Ed Wood, it was the cinema — would make you an interpretive artist of the highest order.

In “Marguerite,” the title character is working on a cruel passion-to-talent ratio. She’s a terrible, screechy, off-pitch would-be opera singer, but she loves Mozart and Bellini and Handel so much that her delusions prevent her from hearing how little she can bring to her pursuits. It’s a movie about a sweet-natured mediocrity and her social circles, from director Xavier Giannoli and written by Giannoli with Marcia Romano.

But it’s more than that. With a sure hand and a slyly sincere tone, “Marguerite” refuses to settle for cheap mockery. It allows this wealthy baroness, living in 1920s France, a graciousness, humanity and gentle pathos that sustain Giannoli’s droll and beautifully acted picture.

“Marguerite” is French fiction based on one American historical inspiration in particular. The socialite and opera lover Florence Foster Jenkins spent decades performing private vocal recitals that her friends and family were too polite to talk about honestly, and in 1944 she made her public debut at Carnegie Hall, to dire results. There’s a movie about her — a broader sort of comedy based on the trailers — coming out this summer, starring Meryl Streep and directed by Stephen Frears.

Giannoli’s film goes its own way, fruitfully, fictionalizing everything and relocating the action to post-World War I France. At the start, Marguerite is hosting a war orphans benefit at the estate of her diffident husband, Georges (Andre Marcon). The party’s crashed by a cynical young music critic (Sylvain Dieuaide) and his monocle-sporting, dada anarchist pal (Aubert Fenoy). There they meet a conservatory student (Christa Theret), a singer of considerable promise and charm. And then they all hear Marguerite sing.

The critic writes a cleverly encoded review, praising the baroness’s vocal attempts to “exorcise an inner demon.” The singer is thrilled and touched by the notice. Georges, reading the review, doesn’t know whether to laugh or cry or simply run back to his mistress. But the spark catches fire, and Marguerite (played with a perfect sense of poise and off-stage grace by Catherine Frot) pours herself into her singing, with the constant aid of her manservant (excellent Denis Mpunga, graduate of the Erich von Stroheim “Sunset Boulevard” school of enablers).

I’m not sure the final 15 minutes are quite right; both the rhythm and the story direction seem uncertain. But every performance interlocks with every other performance. More a dry, high comedy than a satirical one, contrary to The New York Times review’s characterization, “Marguerite” achieves what the protagonist herself never managed: perfect pitch.