One of the primary reasons for the decline in popularity of on-screen sex scenes is the ubiquitous nature of pornography. When individuals can readily access their most intimate desires and fantasies with a simple click, who needs the carefully orchestrated, R-rated “erotic” versions?

As if to acknowledge this, “ Babygirl ,” a drama about a dangerous office liaison written and directed by Halina Reijn (“Bodies Bodies Bodies”), opens with a high-angle close-up of Nicole Kidman straddling an unseen man and panting with pleasure. It looks and sounds a lot like the kind of movie sex scene that would have once been described as “hot.” But as soon as the coupling is over, and the man — Antonio Banderas, as Kidman’s husband — says “I love you,” we see Kidman escape to another room (easy to do in their gargantuan Manhattan apartment), at which point she breathlessly lays down on the floor in front of her laptop and masturbates to a grungy piece of incest porn.

The irony is that Kidman’s character, Romy, is portrayed as a woman who “has it all.” She’s the CEO of her own company — an e-commerce company called Tensile Automation, a sort of advanced Amazon that guarantees same-day delivery by using automated logistics (meaning the entire warehouse is run by robots). She’s got her kind, supportive husband, who’s a prominent New York theater director, as well as two lively teenage daughters (Esther McGregor and Vaughan Reilly). And she’s got her healthy “normal” sex life … and her secret forbidden fantasies, which are what truly excite her. In other words, she has everything; she just doesn’t have everything in one place.

Early on, we see Romy in the office and in the mission-statement videos she makes for the company, where every upbeat word is market-tested, including a reference to how “nurturing” the company is — even though its all-robot setup essentially leads to job losses. (Romy believes she’s liberating people from mundane jobs.) The movie offers a subtle commentary on what’s happening in corporate culture today, but what makes it intriguing is the way that it all connects to Romy’s pent-up sexuality, and to the forbidden office affair that’s about to ensnare her.

Romy, with her “friendly” professional manner, her eyes glued to the information flowing from her phone, is the boss as a highly functional control freak. What she’s yearning for, beneath it all, is the kind of sexuality that’s going to break that control. And the implication of “Babygirl” is that it’s not just Romy. The movie presents us with a society, increasingly reliant on technology and the strict adherence to corporate protocols, where everything is controlled. Which simply fuels everyone’s desire to break free from it.

The young man who is about to ignite Romy’s fantasies is Samuel ( Harris Dickinson ), a newcomer to the company's internship program. This film explores the story of a woman in her fifties who embarks on an affair with a young man barely out of college. Had “Babygirl” been released two decades ago, it would have likely been categorized as a “cougar” fantasy. The initial encounter between Romy and Samuel would have been solely focused on their irresistible attraction. However, Reijn takes a more cunning approach.

Their paths cross during a tour of Tensile’s expansive lower Broadway office space, given to the new interns. As they are led into Romy’s office, Samuel poses a remarkably rude question about the company's robotic premise. Dickinson, a talented actor known for his roles in “The Iron Claw” and “Triangle of Sadness,” with his youthful features accentuated by a jagged haircut, resembles a more blunt Austin Butler. His portrayal of Samuel conveys a sense of dominance, as he declares to Romy before they have even exchanged a proper glance, “I make the rules. By breaking yours.” And this is precisely what fuels the allure. These are undeniably attractive individuals, yet in “Babygirl”, their chemistry revolves solely around the promise of transgression. With each encounter in the office, Samuel confronts Romy with another casually hostile remark, dismissing pleasantries and small talk. His “flirting” is an aggressive assault, and that's why she can't resist its pull.

“Babygirl” transforms into a cleverly honest and captivating film exploring a brazenly “wrong” sadomasochistic relationship. In “Bodies Bodies Bodies,” Reijn crafted a tone of exaggerated satirical slasher pulp, but here she settles into a much more realistic style, and executes it with flair. The film evokes, at times, “Fair Play,” but it’s also a tale of infidelity that pushes genuine emotional buttons, in a similar way to “Unfaithful” two decades ago. And that’s rooted in Kidman’s fearless performance.

Romy embodies a complex blend of identities: mother, boss, defiant adulterer, and trembling sexual supplicant, a living, breathing mood ring. Her character stems from a long-held, concealed truth: those who thrive on wielding power can harbor primal fantasies of sexual submission. For decades, high-ranking male executives have kept B&D sex workers in business, but the corporate gender dynamic hasn't been flipped quite like this on screen. For a while, “Babygirl” feels like a less polished version of “9½ Weeks,” as Samuel chips away at Romy's defenses, notably in a scene where colleagues are enjoying cocktails after work and he sends her a drink...of milk. He's saying, “You're my baby girl.” And when she accepts it, she's essentially saying, “Yes I am.”

When they meet in a hotel room, Kidman oscillates between submission and resistance, and the interplay of emotions on her face is astounding. She allows us to witness the erotic battle that’s tearing Romy apart. But, of course, what’s perilous about this affair isn’t just the S&M aspect. It’s that Romy is shattering every corporate rule that now governs workplace relationships. And the most cunning aspect of the film is how Samuel employs those protocols, and their breakdown, to seduce Romy into crossing the line. The fact that she’s having an affair with an intern from her own company, jeopardizing everything she’s built, is part of the allure. The driving force of Kidman’s performance is that she portrays this reckless abandon as something deeply human: the expression of a woman too compartmentalized to reconcile the different facets of herself. She’s caught in an erotic fever, but it’s one that’s infused with anguish.

Does it all crumble? “Babygirl” follows a traditional structure (and includes one very good earworm, in which the tattooed Samuel dances to George Michael’s “Father Figure”). But one of the film’s strengths is its avoidance of the typical roller-coaster climax we expect from an “erotic thriller.” There’s an old-fashioned moralism at play in movies like “Fatal Attraction,” where the characters are punished for their transgressions. Reijn is pursuing something different — she’s aiming to liberate characters who are too preoccupied with punishing themselves. “Babygirl” takes a few unexpected turns, but that’s because the movie’s ambition isn’t merely to fuel the thriller engine. It’s to capture something genuine about women’s erotic experience in the age of control.