Lurid and tacky enough to be ripped from real (American) life and packaged and scored right up to the edge of campy soap opera, Todd Hayne’s “May December” has that air of sexual transgression that has characterized his most memorable work.

But unlike “Carol” and “Far from Heaven,” the object in telling this story of an actress researching a couple that coupled when she was 36 and he was 13 is almost mocking — equal parts self-serious and ludicrous.

Recycling the unforgettably over-the-top and melodramatic piano score Michel LeGrand composed for the 1971 classic “The Go-Between” kind of gives away the joke.

Built on another fine, brittle performance by Hayne’s muse, Oscar winner Julianne Moore (“Safe,” Far from Heaven,””Wonderstruck”) and a cleverly imitative and “actressy” turn by Oscar winner Natalie Portman, it’s clever in its creepiness even if never quite escapes “soap opera,” to me at least.

And the “camp” only rears itself just often enough to remind us it’s there, adding to the emotional remove of it all.

Moore’s Gracie is a busy bee when we meet her, baking and prepping food to cook at an extended family and friends cookout. We’re bowled-over by the whirl of activity, the children praised, questioned and corrected, the meats handed over to the young grillmaster, Joe (Charles Melton of TV’s “Riverdale”).

Nothing weird here, right?

But Gracie’s conversations, to friends in person and on the phone, give away what’s coming and what happened long ago, at least some of it.

“I told you what happened when I met ‘Judge Judy,'” she burbles. And as this rambling, bayside house is on a coastal George island, we know that “meeting” wasn’t at Ralph’s supermarket.

Elizabeth Berry, a TV star (Portman) is coming, and everybody’s all atwitter. Elizabeth is finishing off a little homework before showing up to chat up, shadow and observe this most unconventional family. And “homework” entails tabloid clippings, book covers, accounts of “giving birth in jail” and everything these two endured — statutory rape charges among them — because then-married Gracie fell for seventh grade hunk Joe when she was 36.

Before playing her in a TV movie, Elizabeth wants to meet them, spend time with their family, question and study them and maybe find “something true” to say about their notorious coupling.

She will gain Gracie’s confidence, even let her apply her makeup the way Gracie wears hers — pale and dewy. She will talk with Joe, who grew up to be an X-ray technician with a passion for breeding Monarch butterflies (Caterpillar/Chrysalis METAPHOR alert!). She chats with everyone from Gracie’s ex (D.W. Moffett) to her maladjusted son who was in the same class with Joe, her lawyer and others who she hopes will inform this search for “something true.”

Perhaps our eager actress is surprised by how these nationally reviled figures — who still get boxes of feces in the mail — are regarded by the locals.

“They’re a very beloved part of the community,” one friend allows. Gracie “always knows what she wants.” And she’s “unapologetic” about going out to get it, especially about her love of 23 years, Joe.

If there’s political commentary in the movie, it’s in that relaxed attitude in a South not far removed from child marriages and broader acceptance of age-inappropriate affairs in a pre-repeal of “Roe v. Wade” 2015.

Portman’s Elizabeth is meant to be our tour guide into this world, into these lives. But she’s hardly an invisible observer. Kids and adults get a little starstruck, and maybe some of them tell her things they wouldn’t ordinarily reveal. She agrees to go to theater class with their teenage daughter, Mary (Elizabeth Yu) where the kids ask about movie sex scenes and playing unsavory characters…like Mary’s Mom and Dad.

As we take in Mama Gracie in her element we can wonder if this fragile control freak is allowing anything said that she hasn’t approved, any interview arranged she hasn’t decided to allow.

The “disgraced seductress” intrigues Elizabeth, but as she sweet talks her way into the “stock room” in back of the pet store where Gracie and Joe consummated their illegal affair just so she can act out how she wants to play the scene, heavy breathing and all, we see her obsession grow and transgressive, “left coast” show business tolerance give way to something more “in character.”

Does Elizabeth want herself “some of that?”

Not every Haynes film (the pollution-fighting drama “Dark Waters” was his last feature) has the sort of theatrical emotions that his films exploring sexuality and relationships and cultural mores do. This seems chillier than most. The stars have an unapproachability in their characters and performances that makes the whole enterprise play like a game in which we aren’t given all the rules.

But Moore, Portman and a believably still-naive Melton make “May December” worth your while, players reaching for “something true” in a story so arch and tabloidy that while it might not only happen in America and only be scandalized in the American South, it never lets us get that “It’s all a joke” out of our minds.

Rating: R for some sexual content, graphic nudity, drug use and language

Cast: Natalie Portman, Julianne Moore, Charles Melton, Elizabeth Yu and D.W. Moffett.

Credits: Directed by Todd Haynes, scripted by Samy Burch. A Netflix release.

Running time: 1:57