In a recent afternoon, Meghann Fahy, one of the stars of the second season of HBO’s “White Lotus,” bounded through the entrance of Mom’s Spaghetti, a nine-day-only “pop-up experience” in SoHo celebrating the twentieth anniversary of the film “8 Mile,” starring Eminem as the rapper B-Rabbit. Fahy considers herself to be an Eminem connoisseur. Her go-to karaoke song is “Stan,” a menacing epic about an abusive loner who is obsessed with a famous rapper. “It’s not his fastest song,” Fahy said. “But I do think, from a storytelling perspective, it is one of his best.” She explained that Eminem karaoke was less obnoxious than the alternative; she’d grown up in southern Massachusetts, where she’d trained to be a professional singer. By eighteen, she was on Broadway, starring in the musical “Next to Normal.” The role’s princessy vibrato didn’t play too well at divey karaoke bars. “I like to give the people what they want, and it is not that,” she said.

The shop bumped a bass-heavy hip-hop track. Fahy, who is thirty-two, with a spray of cheek freckles and swishy strawberry-blond hair, shimmied along. She wore a double-breasted plaid overcoat, a navy ski cap, and an oversized beige cardigan, like Katharine Hepburn if she shopped at Grailed. Ciara Benko, the pop-up’s publicist, asked Fahy about the first time she saw “8 Mile.” “Oh, it was in 2002, and I had, like, a sexual awakening,” Fahy said. “My friend and I had to watch it in a closet, because we were not supposed to be watching it.”

Benko led Fahy to a window serving hulking takeout boxes of spaghetti. “They have plain meatballs and vegan ‘Rabbit’ balls,” Benko said. Fahy opted for the vegan. “I’m a pescatarian,” she said. “Though I have been known to fire down some chicken fingers, depending on my level of inebriation.” Then they headed downstairs, into the “trailer park” (featuring a yolk-yellow neon sign from the film bearing the words “8 Mile Rd. Mobile Court”) and the “bathroom,” a re-creation of the film’s grimy night-club lavatory. They stopped at the mirror where B-Rabbit would psych himself up. Fahy posed with her arms crossed.

Near the exit, Fahy made a beeline for the gift shop. “I lo-o-ove merch,” she said. She picked up a vinyl copy of the film’s soundtrack. “Does it have the rap battles on it?” she asked. She caressed a T-shirt promoting a showdown between B-Rabbit and his nemesis, Papa Doc. She bought two, one for herself and one for Leo Woodall, a British actor she befriended while in Sicily filming “The White Lotus.” “We lived there for, like, two and a half months, and we all hung out with each other a ton, because it was like a ghost town,” she said. (They filmed during the island’s off-season.) She and Woodall bonded as fellow Slim Shady stans. “He can do all the freestyles from the film!”

On the show, Fahy plays Daphne Sullivan, the ditzy, pampered wife of a playboy financier, with a secret knack for playing twisted mind games. The role involves jarring lines about forgetting to vote or splurging on luxury goods, but Fahy delivers them with such cunning alacrity that they reel in more than they repel. “Mike White”—the creator of “The White Lotus”—“just has this insane ability to cast, like, the perfect person,” Fahy said. “I watch the show as a fan, and I see everyone else’s performances, and I’m, like, I cannot imagine anybody but you.” She went on, “I auditioned for Season 1 and got really close.” The role ended up going to Alexandra Daddario.

After loading up a bag with “8 Mile” memorabilia, including a hoodie and a Carhartt hat, Fahy ventured out to the street to eat her promotional pasta. She plopped down on a concrete stoop. The takeout box weighed about as much as a Pomeranian. The noodles were slicked with a red sauce that smelled and tasted like supermarket Ragú. “At least it’s still warm,” Fahy said, shoving a plastic forkful into her mouth. She made it about halfway through the box before declaring that she’d ingested as much Eminem-branded carbs as she could take. “It was pretty mediocre,” she said. “But, also, I kind of wanted it to be?”

Fahy said she’d become a food snob after shooting in Italy. The best thing she ate? “Probably the eggplant parm that I made,” she said, laughing. “A guy who owned this restaurant offered me a cooking class. So I show up, and the restaurant is open. They’re serving lunch. And he’s, like, ‘Just get in the kitchen.’ We just ended up working that day, plating food and serving it to customers.”

Her parm turned out, but Fahy had some residual guilt. “I’m kind of on the fence about it,” she said. “If I was in Sicily, and I went to a restaurant and there was an American girl in the kitchen trying it out for the first time, and I was paying for that?” She shook her head. “I’d be, like, what the F?”