For four years after she left Grey’s Anatomy, Sandra Oh waited. She waited for offers to come in, juicy scripts that could come alive in the hands of her Golden Globe–winning talent. Sure, she did acting work here and there; a lead turn in the indie Catfight, a cheeky supporting role in the comedy Tammy, an arc in the drama series American Crime, a few plays. But there was nothing on the scale of Cristina Yang, the sarcastic surgeon she played on Grey’s for nearly a decade—a standout performance that turned the Korean-Canadian actress into a household name, and earned her five Emmy nominations in a row. The lack of certain offers was, Oh says, heartbreaking at the time.

These days, though, the deeply pragmatic actress says she’s letting go of expectations: “That’s where I’m at. I can talk about the things that didn’t come my way that I think should come my way, but it’s just like—it’s a fuckin’ waste of time.” Besides, her four-year waiting spell eventually led to Killing Eve, a BBC America thriller premiering Sunday about a bored MI5 operative named Eve Polastri—played by Oh—who becomes obsessed with hunting down a psychotic assassin named Villanelle (Jodie Comer). The women are morbidly drawn to each other as they engage in a deliriously good game of cat and mouse.

The show, from Fleabag creator Phoebe Waller-Bridge, is based on books by Luke Jennings; in the series, Polastri is white. When Oh flipped through the script for the first time, she was confused about who the producers wanted her to play, scanning for the inevitable doctor or receptionist role. It was only when her agent told her point-blank that they wanted Oh for the lead that she became aware of how inured she had become to the TV and film world’s brusque treatment of nonwhite actresses. Plum leading parts are usually reserved for white performers; everyone else is brushed to the outskirts of the industry, no matter their caliber.

“It’s like, ‘Oh, it’s so easy! They just called you!’ ” she says of her Killing Eve casting. “Right? In a way, yes, that’s true. But in another way, it took 30 years to get this call.”

In Oh’s hands, Eve Polastri is littered with quirks. She’s the type of person who rushes to a very important meeting late and hungover, squirreling away bites of flaky croissant as she’s debriefed about a vicious new assassin. She is deeply obsessed with murder, enough so that when her husband asks how she would kill him—theoretically(!)—she gives a frighteningly specific response. She’s also deeply obsessed with her newest adversary, a mysterious figure she feels very confident is a woman—though everyone around her brushes off the idea. The assassin is the elusive Villanelle, a young, beautiful Russian woman with the innocent gloss of a Kewpie doll, albeit one that goes dead in the eyes when she has to fake a smile. Villanelle is a practical, physical assassin, never resorting to the classic tropes of a femme fatale who uses seduction as a weapon. Instead, she uses guns, needles, knives, poison. She’s well-rounded, homicide-wise. And her new fixation is Eve. Before long, a dance begins—the hunter and the hunted, the murderer and the murderino. Eve and Villanelle’s bond is a tangle of curiosity and respect that occasionally borders on lust.

“There’s all these things [Eve] doesn’t believe about herself that, in some ways, Villanelle sees! And it’s a good thing!” Oh says. “I think they’re willing to see each other.”

Like many actors, Oh usually avoids watching herself on-screen—but she made an exception for Killing Eve. After devouring three episodes, she can say that the series is exactly what she hoped for. “In the plethora of all that’s out there to watch, actually being something different is so fun,” she says. And Killing Eve really is unique, not least because of Oh’s wide-ranging, witty performance and her kinetic chemistry with Comer.

The only people possibly more excited than her about this show are her parents. Oh speaks fondly of driving around town with her mom and dad one recent day until they found it: a massive billboard for the show with her face plastered front and center. Oh’s parents, who are Korean immigrants, were thrilled. It wasn’t easy to get them to this point: with a lawyer for a sister and a medical geneticist for a brother, Oh says she practically had to achieve this level of fame in order to prove she had made it as an artist. “Koreans are ambitious, man,” she says. “It means a lot to my parents that I do the work that I do and it has the visibility.”

That visibility is a major part of what drives her. For a long time, Cristina Yang was the most mainstream, non-stereotypical Asian character on television, a legacy Oh reckons with on a daily basis. “Young Asian people who come up to me have a certain vibration, and I receive it, and I understand it, and I feel emotional just talking about it,” she says. “I’m here for you. And I’ll continue doing everything I can to fill something that I know you need right now, that we don’t yet have as a community.”

But series like Grey’s are still outliers. The needle has moved very slowly in terms of East and South Asian representation on American television—and film has moved slower still. Oh, for her part, tries to find ways to inject inclusion into the projects she works on. On Grey’s, she noticed that child and teen actors tended to be either black or white; a onetime teen actress herself, Oh says she urged former the show-runners to hire a more diverse swath of young talent. She spoke up in the same way on the set of Killing Eve. When Season 2 rolls around—the series was renewed before its first episode aired—she hopes inclusion will extend behind the camera as well. “That’s vital,” she says.

Though Oh is now comfortable flexing her star power on a set, she’s not necessarily interested in adding more sub-titles to her acting career. Unlike many of her peers in the ever-widening landscape of television, she hasn’t sought out writing, directing, or producing opportunities (though she is an associate producer on Eve). She ignores dailies; she leaves editors alone. There’s an almost Spartan edge to her discipline—which sets her apart from, say, her former Grey’s co-star Ellen Pompeo, who recently drew applause for telling The Hollywood Reporter about her decision to pivot toward producing, and her struggle with negotiating a higher salary. Oh was among the piece’s fans: “I totally understand and remember that struggle for her,” she says. “It’s really good that she feels full circle about that. That she feels righted now.”

When the subject naturally shifts to her own Grey’s salary negotiation, Oh takes a deeply pregnant pause. “I don’t see it the same way, in my experience . . . it’s complicated,” she says, dropping the word like a hundred-ton weight. “It’s too complicated, you know what I mean? The best answer for that is Rashomon”—the 1950 Akira Kurosawa thriller that follows various witnesses and suspects who give different accounts of what happened to a murder victim.

Oh is on a new precipice now. She thinks about power a lot: how to access it, how to wield it. How to protect her career by picking projects carefully, even when the offerings are sparse.

“The four years of actively waiting by doing the things that I love . . . it was my choice to do three plays. It was my choice to do American Crime, you know?” she says. “Actually being able to exercise your own choice can bring about greater opportunity. I think it’s just as important what you say no to as what you say yes to.”

She grins, musing about Killing Eve just on the horizon.

“I hope it was worth the wait.”