The serene overheated-via-slow-simmer melodrama “Bonjour Tristesse” leaves its 1950s origins behind in a shimmering new screen adaptation by first-time writer/director Durga Chew-Bose.

Based on the most famous work of French college girl novelist Françoise Sagan, this tale of privilege, petulant manipulation, sex and “sadness,” which is all our guilty, spoiled narrator can summon up, “Tristesse” gives Chloë Sevigny her best role in years. And it shows off the sunny, summery south of France (Cassis, on the Western edge of the Riviera) in all its glory.

This immaculately lit and shot (by Maximilian Pittner) and gorgeously designed (by François-Renaud Labarthe, who did “Clouds of Sils Maria”) and costumed (Miyako Bellizzi) potboiler does justice to Sagan’s “ultimate beach novel” source, even if it never escapes that label.

“Hello Sadness,” as the title translates, has been filmed a few times before, most famously with Jean Seberg, Deborah Kerr and David Niven in the late “Peyton Place” 1950s. Here, Lily McInerny plays the gamine transitioning into cranky coquette Cecile, a petite young teen summering on the coast with her wealthy, indulgent dad (Claes Bang of “The Square”).

Widowed dad has taken up with a vivacious dancer, Elsa (Nailia Harzoune), and Cecile is having a summer romance with the just-as-stylishly thin local Cyril (Aliocha Schneider). But father-and-daughter are the truly committed “couple.” Her mother died a dozen years before, and her father gives Cecile all the attention — they even play solitaire together — and all the latitude any spoiled teenager could want.

They share cigarettes and wine, because, hey, France.

Cecile’s fascination with dad’s free spirited dancer is disturbed when an old friend of both her parents, the Paris fashion designer Anne (Sevigny) comes to stay with them.

Anne is always perfectly put together. Reserved, sophisticated and droll, she’s a blast from father Raymond’s shared past with his late wife.

“We were all obsessed with each other,” Anne tells Cecile about their youth. As the source novel was scandalous for its sex, we can infer from that what we want.

And in any event, it isn’t long before dear old dad is “obsessed” all over again. And the feeling is mutual.

Cecile decides to break Anne and father Raymond up. And in logic that only ever appears in the movies (and their source novels), Cyril and even Elsa join in that conspiracy.

First-time writer-director Durga Chew-Bose fixates on the arid interests of the idle (not so idle in talented Anne’s case) rich. This Canadian co-production resembles many an upper class/elite French tale in the omnipresence of books, with no TV sets in sight, and in the airless vapidity of the conversations of the pretentiously carefree.

“What do you think about when you try not to think about things?” at least sounds profound.

Bang leans into his handsome dash, with leisure costumes that would flatter anyone, and the character’s self-absorbtion, making Raymond’s abrupt has-his-choice-among women tumble for Anne believable.

McInerny hides any hint of teen rebellion, a child most comfortable among adults thanks to her indulgent Dad, but seriously smitten by the willowy, more experienced Cyril. We get lots of closeups of her Hathaway-meets-Hepburn throwback beauty. As performance, we need to sense more of the wheels turning in Cecile’s “I want things my way” head as she attempts to reset her father’s romantic attentions. The film’s leisurely pace allowed room for that, had Chew-Bose chosen to highlight it.

Sevigny, photographed with care as Anne dresses (her own designs), touches up her perfect lipstick and secures the meticulously tight bun in her hair with a pricy silver hairpin, is a portrait in professionally acquired privilege. Of course she drives a Saab convertible. What else would do?

In this and so many other ways, writer-director Chew-Bose gets the externals right. But every immaculately dressed set, every perfectly composed shot, traps her adaptation in its genre and its staid 1950s origins. This melodrama has a Douglas Sirk sheen with Riviera settings. But as we learned in “Far from Heaven,” even Sirk needs to be updated for the scandal of it all to sting.

There’s nothing “scandalous” about the sex and the shifts in affection, and the intended “shock” of the melodramatically inevitable consequences to all of this manipulation isn’t shocking in the least.

Only the underreaction of the many rich, guilty parties — conspirators and the easily manipulated — really hits you. A resigned sigh of “Hello, sadness” is all the consequence-free can manage by way of regret, remorse or apology.

Rating: R, sex, smoking

Cast: Lily McInerny, Claes Bang, Nailia Harzoune, Aliocha Schneider and Chloë Sevigny

Credits: Scripted by and directed by
Durga Chew-Bose, based on a novel by Françoise Sagan. A Greenwich Entertainment release.

Running time: 1:50