On stage, drag artist Aphrodite Banks is a femme fatale: Caked in war paint, with a waterfall of braids whipping around her waist, she’s possessed of the white-hot glare and forthright confidence to match her Amazonian height and bearing. Off stage, as Jules, he’s simply femme: that term for gay men who present or express themselves in a more feminine way, too often used as a slur or a dismissal even by their community brethren. (Open up a cruising app like Grindr and see how frequently “no fems” comes up as a requirement.) The former identity connotes swaggering strength; the latter, to many, delicate weakness. How those associations and stigmas battle each other in one man’s body is the driving conflict in “Femme,” a tense, sometimes startling revenge drama from British freshmen Sam H. Freeman and Ng Choon Ping.

A pair of sensational performances by Nathan Stewart-Jarrett (“Candyman”) and George MacKay (“1917”), locked in a nervy duet as two men with virtually nothing in common but their sexuality, represents the chief selling point for this stylish, commendably uncompromising fusion of genre fireworks and measured, thoughtful character study. The stars also hold the film steady and emotionally credible when a hitherto sturdy screenplay, by the novice directors, makes some wild, wayward plotting moves in the home stretch. Such eminently forgivable first-feature glitches won’t stop “Femme” from racking up festival appointments — particularly in the LGBTQ+ sphere — following its premiere in Berlin’s Panorama strand, while edgier arthouse distributors are also sure to want in.

For Stewart-Jarrett, who has been on the British next-big-thing radar since his leading turn in the sci-fi teen series “Misfits” over a decade ago, “Femme” is a long-overdue feature showcase for his supple, adaptable gifts: The film hinges on his believability in a complex spectrum of gender guises and archetypes, and his intense vulnerability even at the character’s most performative and walled-off. We’re introduced to him first as Aphrodite, dauntless and unshakable as she struts through a Shygirl lipsync at a hip East London queer club. Yet after the show, as Jules dashes to the convenience store down the road for cigarettes, his flamboyant Aphrodite costuming feels not like armor but a target, open to attacks from everyday bigots.

Sure enough, at the store, a group of thuggish young men taunt him. Jules gives as good as he gets, picking up on the mixture of loathing and intrigue in the stare of ringleader Preston (MacKay), and suggestively baiting him back. A fight ensues, shot and cut as a blurry, brutal tornado of limbs, skin and blood; stripped and viciously lacerated, Jules is the loser. For weeks afterward, to the consternation of his outgoing friend and housemate Toby (John McCrea), he withdraws into himself.

When he ventures out again, it’s into the comparatively secluded shadows of a gay sauna — mostly shooting at night, or in charged, low-lit interiors, DP James Rhodes is wise to the different textures and colors of darkness that distinguish an air of safe or seductive privacy from one of invisible threat. In the locker room, he agains encounters Preston: bristling with sexual aggression and self-loathing, and oblivious to the identity of the man he brutalized weeks before. They have rough, anonymous sex, and exchange numbers.

At first, Jules’ motives in this literal case of sleeping with the enemy seem clear-cut: He’s after a revenge-porn video, sure to ruin his closeted tormentor’s life and social standing if it leaks online. But the thorny point of fascination in “Femme” is not this mission but his increasingly ambiguous investment in it, as curt, thrusting trysts with Preston, a superficially moneyed dealer, become dinner dates and, in time, halting, anxious gestures of affection. Is Jules also an expert performer away from the club spotlight, dispassionately stringing along his prey by playing sweetly submissive? Or does some internal part of him actually yield to Preston, whose short fuse and emotional immaturity can’t entirely conceal the catharsis he feels at being able to live out his identity in one man’s presence?

Even as the narrative is somewhat clunkily engineered toward a grand reveal — one in which characters conveniently appear and disappear to speed things along — Freeman and Ping never force a conclusion. Neither does Stewart-Jarrett’s lithe, crackling performance, which shimmies up and down the various degrees of masculinity required for his increasingly fraught project: jockishly straight in the presence of Preston’s friends, femme and taciturn when they’re alone and, in one significant pivot, icily dominant when he senses other desires afoot between them. He gets a vital assist in this regard from Buki Ebiesuwa’s slick, canny costume design, which is keenly attuned to the roles and codes of gender, attitude and sexual power that can be stitched into both casual streetwear and flamboyant stagewear. Viewed in three different iterations, a simple saffron-yellow hoody becomes a more loaded and versatile garment than you might ever imagine.

Stewart-Jarrett is superbly matched by MacKay, an actor whom the industry sporadically attempts to fashion as a gung-ho leading man — and who always seems more at home when drawn into darker, more perverse territory. His casting here plays cleverly on that very duality: Never standing but posing, stamped up to the throat with laddish tattoos, with a slurring voice suffocated with pent-up rage, he’s a full-body clenched fist of straight-acting aggression, only gradually permitting himself erratic moments of honesty and good humor in Jules’ presence. From Preston, a single brief, darting peck on the lips seems a transformative miracle, though MacKay never entirely hides the softer, unexpressed boy in a terminally volatile man. “Femme” neither sets out to forgive or redeem this bully, merely to outline all his warring, unresolved parts — as copious and chaotic as Jules’ splintered identities, lashing violently outward rather than inward.