The first mystery of “Stars at Noon” is just who and what this character, Trish Johnson really is?

She tells one and all she’s a “periodista,” a journalist. Since she’s paying for her drinks with cordobas, we can guess she’s in Nicaragua. And since she drinks a lot, maybe we buy the “periodista” label.

But she gives no sign she takes notes or photographs. There’s little about her slinky sun dress that says “professional.” Well, not that profession.

That Brit she’s met in the bar of the swank Hotel Intercontinental asks her directly, “Are you for sale?”

“I’m press.” But she doesn’t seem offended, just claiming the proper credentials.

“We’re all press here,” he shrugs. One drink later, things turn back to transactional.

“For a price I’ll sleep with you.”

Mysteries matter in the films of Claire Denis, who makes movies in which story drifts into the background as characters, settings and predicaments move to the fore. Think of her “Chocolat,” French and set in Cameroon, or the Robert Pattinson father-daughter-in-space tale “High Life,” or “White Material.” It’s the patient, meandering storytelling, the ordinary characters who make tenuous connections and conjure up the unexpected, the dreamy tone that sticks with you.

Margaret Qualley plays Trish, bringing that laid-back, go-with-the-flow vibe she brought to “Once Upon a Time…in Hollywood” with her. We don’t know how Trish got into Nicaragua. But we can tell she’s stranded there and that this is getting to her. The “how” and the “why” only become a little clearer with time.

An Army lieutenant (Nick Romano) she has a regular thing with gives her a post coital chewing out.

“You’re NOT a journalist!” “I am TOO!”

A call to a guy she regards as her editor/”employer” (John C. Reilly) back in the States sets her and us straight. No, he’s not sending her money. No, she’s not doing a “piece” for him.

“Just admit to yourself that you’re not a journalist.”

But this Englishman (Joe Alwyn of “Mary Queen of Scots” and “Billy Lynn’s Long Halftime Walk”) she’s watched hanging around with “cops” or “Costa Ricans” intrigues her. There’s an election going on, which she expects to be delayed, whose delays have something to do with why she can’t get out of the country. And the Brit, who might quip unflatteringly about her sex worker status, can meet her price “in DOLLARS.” He might be trouble, but he could be her ticket home.

The film, based on a Denis Johnson novel, serves up Qualley as the prettiest “Ugly American” we’ve ever seen — sexy and unabashed, semi-fluent in Spanish and prone to “when American tanks come and CRUSH your country” tirades when she runs into the petty corruption, the lax Central American “mañana” attitudes and Catch-22s of being stuck in a place with no easy way out.

Somebody broke her phone. Somebody took her passport. And that’s before she takes up with this sketchy, apparently-married and somewhat posh Brit with linen suits and a gun, who says he’s here for “consulting” with an oil company — in the middle of another harrowing election in a corner of the world where that’s the norm.

Denis keeps the intrigues murky and the motives murkier as our couple’s predicament grows more dire. I never bought into the love story supposedly budding here, but that’s kind of the point. Who is using whom?

Is Trish really the one with the spycraft in this “partnership,” clever enough to know how to dodge that tricked-out Jeep full of “Costa Ricans?” Is Daniel in over his head, too?

Costa Ricans seem to be everybody’s favorite villain in Nicaragua, CIA stooges doing the gringos’ dirty work. But that doesn’t mean the “real” CIA won’t show up. He (Bennie Safdie) may be obvious, but he’s not going to admit to owning any part of Trish and Daniel’s predicament, or answer a single direct question, no matter how many ways you ask it.

That diffuse plot and emotional disconnection between the leads creates a remove in the film that keeps it at arm’s length. There are coherence issues as well.

But Qualley conjures up another loose, louche and sometimes shoeless (A jab at Tarantino?) free spirit, this time one drifting through a situation whose difficulties she acknowledges even as she tries to ignore the perils.

As “Stars at Noon” unfolds, Denis summons up memories of lots of movies set in this part of the world or any part of the Third World where elections are held and The Game of Nations is played. The foreigners come in and some locals die, and then the foreigners leave and no one really knows if anything was made better or worse except for the dead. And nobody’s asking them.

Rating: R for sexual content, nudity, language and some violence.

Cast: Margaret Qualley, Joe Alwyn, Nick Romano and Benny Safdie

Credits: Directed by Claire Denis, scripted by Claire Denis and Andrew Litvak, based on a novel by Denis Johnson. An A24 release.

Running time: 2:14