Keri Russell doesn’t remember relationships other than Matthew Rhys (Exclusive)

IN The DiplomatKeri Russell plays an American ambassador married to a diplomat. Although it may sound glamorous, Kate Wyler (Russell) and her husband Hal (Rufus Sewell) are not often examples of a perfect marriage.

Russell, 48, describes Wyler’s relationship as “complex.”

“This season, it feels kind of heartbreaking,” she tells PEOPLE. “It feels very mature and like the realities of knowing someone for so long. But with Kate and Hal, it’s not one without the other. It’s so intricate that it’s part of their attraction.”

Russell has real-life experience working with long-term partner Matthew Rhys, who she started dating in 2014 at the start of their run in The Americans. She and Rhys, 49, welcomed son Sam in May 2016.

“It can be a really nice shorthand because they know what work is for you, but it can also feel like a lot at times,” Russell says of having a significant other working in the same field. “But it can be nice to have someone who does something completely different, so that there is a break. But I’ve been with Matthew so long that I can’t remember any other relationship.”

Season 2 of The Diplomat takes place in the aftermath of an explosion in London that injures Hal and some of Kate’s colleagues. “I think it was just as surprising to us when we read it,” Russell says of Season 1’s shocking conclusion. “We had no idea that was where it was going.”

After realizing the blast came from the British government, Kate begins to wonder in season 2 “who she can trust and who she can’t trust,” Russell says.

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Kate is also still considering putting her hat in the ring for the job of Vice President of the United States. “All of that is percolating, but the introduction of (Allison) Janney’s character really complicates the mix of it all,” Russell says.

Janney, 64, joins Season 2 as Vice President Grace Penn. Russell told PEOPLE at PaleyFest 2024 that she “was nervous, a little bit” about Janney joining The Diplomat because “she’s amazing and so good.”

“But she’s everything you want her to be,” Russell said. “She’s gracious and funny and smart and cool.”

The Felicity says alum The Diplomat season 2 launches days before America’s first female vice president runs for the highest office in the land, an “unbelievably creepy” coincidence.

“We did this a year and a half ago, before any of this,” says the actress. “It’s just that it’s worked in our favor a lot.”

Season 2 will be six episodes compared to Season 1’s eight — but The Diplomat was already renewed by Netflix for a third season earlier this month. The Diplomat creator, showrunner and executive producer Debora Cahn Tudum said that season 3 will see Kate live “the special nightmare that gets what you want.”

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The Diplomat season 2 premieres Thursday, October 31 on Netflix.