Three days before the first preview performance of her first Broadway production, the playwright Selina Fillinger perched in the middle of the empty mezzanine of the Shubert Theater, peering down upon the set. “I’m sorry, I can’t look away,” she said. “It’s like a crew of fairies and angels, just making things happen.”

Down below, the crew building the set was buzzing around a re-creation of a women’s restroom in the White House — star-studded carpet, cream and gold wallpaper, coin-operated tampon dispenser. “It’s so specific,” Fillinger said of the tampon machine. “And it would be paid.”

Fillinger’s new play, “POTUS,” is a comedy about seven women in the inner circle of the president of the United States. It takes place on a day when the president’s various sex and sexism-related scandals are blowing up so spectacularly that the women in his life are prompted to take increasingly desperate measures to keep his administration afloat.

The idea began developing in Fillinger’s mind during Donald Trump’s run for office. “I was fascinated by the women in his orbit,” she said. And she noticed that, with every new headline about a man abusing women — Harvey Weinstein, Jeffrey Epstein — “there was always at least one woman, right there at the elbow.”

The result is a farce about women’s relationship to male power — how they access it, what they are allowed to do with it, and who else they subjugate along the way. “I love farces, but they typically rely on sexist and racist tropes,” Fillinger said. So she wrote a comedy about women struggling to adhere to the rules of the patriarchy, which “literally causes a farce on a day-to-day basis.”

In crafting the play’s characters, Fillinger wanted to create the most combustible combination — among them are the president’s weary first lady, Margaret (Vanessa Williams); his perfectionist personal secretary, Stephanie (Rachel Dratch); and his cocky convicted-felon sister, Bernadette (Lea DeLaria) — and dropped them onto a White House set that rotates dizzily like a turntable as the crisis mounts.

As for the president, he is a cipher, appearing in the play only as limbs jutting occasionally into view. “I was interested in purposefully and consciously failing the Bechdel test,” Fillinger said, referring to the challenge popularized by the cartoonist Alison Bechdel that a movie ought to feature two women who talk to each other about something other than a man. “If you take the man out of the room, patriarchy still exists and we still play by its rules.”

Also, she found the president character too tedious to actually write. “He’s an amalgamation of so many presidents,” she said, “and also several men that I’ve done group projects with in high school.” The play’s full title is “POTUS: Or, Behind Every Great Dumbass Are Seven Women Trying to Keep Him Alive.”

When Trump announced his candidacy, Fillinger was an undergraduate at Northwestern University. Now, at 28, she is building a notable body of work, and her farce is being lifted straight to Broadway without an out-of-town tryout. Even as she prepared to open “POTUS” in New York, she was writing for the Apple TV+ series “The Morning Show” in Los Angeles; she joined the writer’s room for its third season and has managed both jobs by flying cross-country and back, sometimes every weekend.

When I met Fillinger on a Monday morning, she was jet-lagged and unfed in a plum jumpsuit and pale purple face mask, a look she described as “chic mechanic.” We talked until she politely announced that she should probably locate the nearest Starbucks instant oatmeal or “I might pass out.” When I asked about her relationship to her own success, she said, “I really didn’t expect it,” then joked of an alternate life: “I thought I was going to spend my early 20s WWOOFing or whatever.” (WWOOFing: visiting farms through the World Wide Opportunities on Organic Farms program.) “It has been a dream, and also, it has been a tremendously steep learning curve.”

FILLINGER WAS RAISED in Eugene, Ore., “by hippies in the woods,” she said. Her father is a sustainability-focused architect, her mother is a social worker who works as a partner in her father’s firm, and Fillinger grew up without television, except for the occasional “Sesame Street” episode and a VHS box set of Charlie Chaplin movies she watched when she was sick. “I read a ton and I wrote a lot of stories and I played a lot of pretend in the woods next to my house,” she said.

When she arrived at Northwestern planning to study acting, “it was an intense culture shock,” she said. “There were all these kids from LaGuardia” — the New York performing arts school — “and they knew all the playwrights’ names, and all the directors’ names, and all the actors’ names, and they had all grown up going to Broadway shows, and I had no awareness of any of that.” But she now sees the upside to having waded into the theater world “when you don’t necessarily know what is being done, and what is not being done.”

As a sophomore, Fillinger took an introductory playwriting class that she found so difficult she assumed it would be her last. But the professor, Laura Schellhardt, encouraged her to submit her work to a university-wide playwriting festival, and Fillinger was selected.

The play was based on a 2013 news story about a Canadian bar that serves a shot garnished with a mummified human toe, and the American man who walked into the bar and swallowed that toe. At the time, “I didn’t know if I belonged at Northwestern. I didn’t feel, necessarily, good enough to be there,” Fillinger said. So she transplanted the story to a fictional Oregon town, and shaped the bizarro news item into a drama about a middle-aged woman fighting to save her bar from being bought by an outsider — a big-city guy whose initial display of dominance over her is to gulp her prized appendage.

When Fillinger first entered that class, “she came in and identified as an actress, and she said that several times,” Schellhardt said. “The second she took ownership over the piece, her hold on the identity of being an actress began to loosen. She could tell her own story and not just to be an instrument for someone else’s story.”

News stories became a tool for Fillinger — a snapshot of the culture that she could twist into new meanings and steer into unexpected directions. As a senior, she took part in a Northwestern program meant to simulate a play commission, and worked with the Northlight Theater in Illinois to develop “Faceless,” inspired by the story of a white woman in Colorado who is recruited to join ISIS through an online network. The simulation turned real when Northlight staged the play in 2017.

Later, her 2019 play, “Something Clean,” a Roundabout Underground production, imagined the parents of a college student convicted of sexual assault in a scenario modeled after the Brock Turner case. After reading Turner’s parents’ statements in that case, “I was just fascinated by the cognitive dissonance that would have to go into their survival,” Fillinger said; the play imagines the mother shielding her identity so she can volunteer at a rape crisis center. The Times critic Ben Brantley called it a “beautifully observed, richly compassionate new drama,” adding that Fillinger “uses traditional forms to frame toxic contemporary subjects” and “keeps readjusting our point of view” along the way.

Fillinger is still affected by current events, but “you don’t necessarily see the stitching as much” in her more recent works, she said. In “The Collapse,” commissioned through the Manhattan Theater Club’s Sloan Initiative for developing new plays about math and science, environmental devastation plays out in miniature in a California apiary, where a bee researcher is dying alongside her hives. When it came time to write “POTUS,” she said she didn’t focus on any particular political figures. “I really didn’t feel like I needed to do any research,” she said. “I have been all of those women at some point.”

All of her plays bear certain imprints: they are interested in interrogating women in power, in finding human tenderness and absurd comedy even in great tragedies, and in placing several generations of women in conversation.

“It’s a shame that people stop writing love, sex and violence for women after a certain age,” Fillinger said. But exploring women at middle-age and older, as she tends to do, is also a canny defense against those who might reduce a young woman’s work to mere autobiographical stenography. When she does write a 20-something woman, “everyone projects assumptions upon that character,” she said. “All of my plays have so much of me in them, but not necessarily in the ways that you would expect.”

AT A TECHNICAL REHEARSAL the week before previews were to begin, the “POTUS” cast practiced on the rotating set for the first time. Under a bust of the suffragist Alice Paul, Dratch, wearing nude shapewear and a lace dickey, writhed on the floor in an inflatable pink inner tube as DeLaria stomped around in camo cargo shorts and a T-shirt that read “SHUT UP, KAREN.” Lilli Cooper, playing a White House reporter, was strapped to a portable breast pump affixed to bottles sloshing with milk; both Cooper and her character recently had a baby. As the set rotated, Suzy Nakamura, who plays the White House press secretary, raced among the rooms to hit her cue at the briefing room podium and stumbled over the president’s disembodied legs, which had accidentally been left splayed on the floor. The cast fell into laughter.

“When it gets toward this time of night, they get tired and they get hysterical,” the director, Susan Stroman, said; it was 9 p.m. and nearing the end of the day’s second rehearsal stretch. “Sometimes we laugh so hard that we cry and we have to stop.”

Stroman said that when she first read the play, she was startled to find a farce that put women not in secondary or tertiary roles but primary ones. “I couldn’t believe that it had all these things going for it, that it was really funny,” she said. Then she met the playwright, and “I couldn’t believe she’s 28,” said Stroman, a five-time Tony-winner who directed and choreographed “The Producers.” “She’s an old soul. She carries the spirit of women who have come before her.”

If Fillinger were to play a “POTUS” character, it would be Stephanie, the type-A personal secretary who is always subverting her own self-doubt into an exacting performance of perfectionism.

She knows that her early success means that she is leaving a very public trail of the emotional and intellectual state of her 20s. Early works are “time capsules of you — sometimes in a good way,” she said. “But they also hold all of your blind spots, and all of your little work-in-progress moments, all of your ignorance and all of your youth. It’s so mortifying to have yourself, frozen at 22, out in the world, just being” But that’s been a gift, too: “I’ve been forced to become not so precious.”

As “POTUS” nears its opening, she is still tinkering. “I’ve been reworking the ending a lot to try to calibrate the tone,” she said. “POTUS” drives frantically toward a shift among its seven women, who begin to question why they are working so hard in the service of male power. But how that change will shake out — and what it will cost — is somewhat open to interpretation.

Fillinger’s relationship to optimism in her work, she said, is complex.

“As a young person and a woman, I’m expected to perform hope for people, without having the luxury of expressing my rage,” she said. “But I feel like rage can be hopeful as well.”