“She’s losing control again,” warns a tagline on a promotional poster for “Boarding Gate,” one that depicts Asia Argento in a feline crouch, wearing only a skimpy bra and underwear, high heels, and a Luger pistol. But it’s not just Ms. Argento’s character in Olivier Assayas’s new film that we’re meant to consider. Aside from referencing a song by Joy Division, one of the pop-savvy director’s favorite bands, the slogan alludes as strongly to Ms. Argento’s reputation as a hell-on-wheels performer who lives dangerously close to the edge, blurring the distinctions between screen persona and carnal actuality.

Perhaps it’s a bit of a sidelong wink as well, since Ms. Argento’s performance in this mood-altered international caper is a tour de force. She’s in such command of her character that every instant onscreen is a flickering signal from a convoluted psyche. As Sandra, a former call girl in a tense on-again, off-again affair with Miles, a debauched American businessman in Paris (Michael Madsen, adding cuff links and pressed collars to his hard-boiled repertoire), the lyric she most immediately evokes is Elvis Costello’s: “She’s been a bad girl. She’s like a chemical.”

And to Mr. Madsen’s Miles, she’s irresistible. Now divorced and faltering in his import-export business, he’s become “the perfect cliché of bygone times” and clearly wants to get his mojo working. Unfortunately for him, Sandra’s the only one who does the trick, as we learn in their acidic recollections of all the epic degradations she’s suffered to please him. Or did they please her, too? Ms. Argento, daughter of the Italian filmmaker Dario Argento and a director in her own right, struts and slumps along the edge that separates empowerment from abuse and keeps us guessing about Sandra’s motivations. They aren’t made much clearer when the film posits her at the pivot of a bizarre love triangle with a Chinese couple (Carl Ng and Kelly Lin), whose own import-export ambitions propel them to use Sandra even more cruelly than Miles, and at his eternal expense. The narrative twists, which also involve drug deals gone bad and Sonic Youth bassist Kim Gordon as a steely Hong Kong lady boss, are kept purposely unexplicated by Mr. Assayas.

The 52-year-old French director has fashioned the film as a kind of sequel to 2002’s “Demonlover,” a kicky, borderline-facetious romp through the secret world of high-stakes corporate espionage, littered with S&M kink, catfights, and a naked Chloë Sevigny playing video games. Equally dreamlike, yet focused through Ms. Argento’s performance, “Boarding Gate” jettisons the silliness but keeps the globalist framework and the jittery, fractal camera movements. Against this backdrop, Sandra becomes both hunter and prey, avenging angel and little girl lost. The dualities become fiercely pronounced in a galvanizing 25-minute sequence with Mr. Madsen, in which the two ex-lovers circle each other as if they were dueling jungle cats on “Animal Planet.” It’s exactly the kind of scene Ms. Argento was born to play — fragile in one breath and lethal in the next, as her co-star manifests a perfectly self-indulgent male ego caught off guard by feminine ambiguity. Kiss, kiss. Bang, bang.

As the film shifts to the Hong Kong streets, where Sandra flees after the inevitable bad things happen, it’s Mr. Assayas who seems to lose control. The desire to shoot a genre thriller in his favorite part of the world leads to a lot of fast and dirty handheld footage of Ms. Argento running, gunning, stalking, and yelling, but the technique dissipates the tightly coiled anxiety of the film’s first half, even though it might intend to ramp up the dynamics. There are some lovely interludes for an excerpt from Robert Fripp’s and Brian Eno’s 1970s ambient-noise classic “No Pussyfooting” to mirror Sandra’s hypnagogic state of mind, but perhaps too much is lost in translation. Still, the actress is riveting throughout, delivering a major performance in a deliberately minor film.