“The Diplomat” Casting Director Julie Schubert on Building a Razor-Sharp Ensemble Around Keri Russell

Keri Russell has been incandescent through three seasons of The Diplomat, playing the disarming, charming, ferociously intelligent title character Kate Wyler while earning two Best Actress Emmy nominations along the way. Slated to air season 4 on Netflix later this year, The Diplomat thrives not just because of Russell’s star power but also because the witty supporting cast keeps up with her every step of the way, mired as they are in backstabbing, romance, and treason. In addition to the original ensemble, Allison Janey and Bradley Whitford turned up the heat in Season 3, reuniting with The Diplomat creator Debora Cahn following time spent together on Aaron Sorkin’s The West Wing.

Cahn’s Emmy-nominated drama initially came together after the writer/producer enlisted casting director Julie Schubert to find actors capable of doing justice to her rat-a-tat dialogue. “When you have material of that quality, you kind of have your pick,” says Schubert, who won an Emmy for casting House of Cards and later worked on Marvel shows including Daredevil and Jessica Jones.

Speaking from her home office in New York City, Schubert explains why she picked British actor Rufus Sewell to play an American, offers her thoughts on color-blind casting, and reveals the one thing she values most when evaluating auditions. 

You hit it out of the park when you cast The Diplomat.

Thank you.

Three seasons and two Emmy nominations in, the core ensemble feels extraordinarily cohesive, given that The Diplomat marked the first time you worked with Debora Cahn, right?

It was the first time, yeah. Absolutely.

So, what was your getting-to-know-you process like in pitching your services to Debora Cahn?

Truthfully, I just threw myself at her feet and proclaimed her brilliance because I hadn’t read a script that good in such a long time. When I did the interview with Debora, I said some really ridiculous things about gnawing off my right arm [for the opportunity to cast the show]. I’m just glad she did not get too scared of me, because I can imagine that happening [laughing]. But no, I just got really lucky. Debora writes characters so well that when you’re casting, it really speaks to you in a way that I think organically tells you who should be playing the character. Creatively, we were on the same page.

You won an Emmy for casting House of Cards, another political thriller. Did that show get discussed as a reference point?

There was no conversation about House of Cards because it’s such a totally separate entity, a different texture. For us, it was all about trying to tell this story through the seasons and who the best candidates would be to do so.

When you came on board, did Debora already have Keri Russell in mind to play U.S. Ambassador to the U.K., Kate Wyler?

Keri was absolutely the first person on our list, but whenever you start a casting process for any show, you put together a long list of people to discuss. It’s not just the show creator; you’re also in partnership with your studio, which [in this case] is Netflix. Everyone needs to be aligned creatively in that process. But Keri Russell jumped off the page immediately.

The British actor Rufus Sewell plays Keri’s very American husband. How did you decide on him as the guy who should be Hal Wyler?

Again, it was all on the page. Hal Wyler’s character is so rich and interesting, we’ve started thinking about who would be a great foil for Keri in the role of Kate? Who would push her, who would challenge her in ways that make an exciting dynamic exciting?

For all those reasons, Rufus Sewell comes to mind.  

Well, the thing that Rufus has is… I mean, he’s so f****** charming and so funny, and, like, off the cuff, and great. For a long time, people just viewed him as a villain because he’d been in The High Castle and things like that. But I’ve always been a fan. I cast him in [2023 Netflix heist series] Kaleidoscope. And he did this turn on The Marvelous Mrs. Maisel that showed the humor and all of that little crackle which people hadn’t necessarily seen recently.  

Rufus Swell told The Credits last year that he met Keri for the first time on the set of The Diplomat in London. So, no chemistry read?

No chemistry read. There is something to be said about understanding an actor’s style, how they work with others, their reputation in the business—all of that gives you a good indication of whether or not they’re going to work well together. Knowing Keri’s beautiful work and her reputation, and Rufus’ beautiful work and his reputation, we trusted that they would find their footing together, which they have really built over time. I think it sizzles.

In The Diplomat, Black actors Ato Essandoh and David Gyasi portray Deputy Chief of Mission Stuart Hayford and British Foreign Secretary Austin Dennison. It’s interesting that there are no backstories or plotlines that deal with the color of their skin. 

I think we live in a multicultural world, and that should be represented on screen. I love that we’re not commenting on race in a show where, in certain ways, that doesn’t need to be commented on. There’s no reason that someone has to be white or black or Asian, or Latino or any of these things. These are smart, driven, interesting, layered characters who should be played by the best actor for the role.

What was your process for selecting Ato and David?

Specifically for the UK, I want to be very clear that I have collaborators in Lucinda Syson and Natasha Vincent. They’re brilliant casting directors who are responsible for the British cast, and they brought in David Gyasi to play Austin.

Playing Stuart, Ato Essandoh seems well-suited as the always-sincere boyfriend to Ali Ahn’s acerbic CIA station chief Eidra Park. What made you think of Ato for this role?

I’ve known Ato for many years, from back when I was an assistant. He’s the kindest, smartest, most lovely, hardworking guy, and just pure hearted. When I read the script, it was Stuart’s pure heat that resonated for me. Just like we had lists for all the characters, we had a list of actors for Stuart, but I think we got it right. It had to be Ato.

Allison Janney makes a grand entrance as the American vice president toward the end of Season 2. She and Bradley Whitford figure heavily in Season 3 as the intimidating Grace Penn and her laid-back husband, Todd. When did you guys orchestrate their roles in this show?

From day one, the conversation was not if we find this space for Allison and Bradley, but when we find it.

Oh really?

When you have actors of that caliber who are a joy to work with, why wouldn’t you want to keep working with them in some capacity? They’re both incredibly busy, so, obviously, their schedules had to work out in their favor. But we found a way to make it all work, which was really exciting.

It’s fun to see the same actors play completely different characters, with Bradley Whitford playing this “beta male” kind of guy.

Yeah, first husband. 

Both actors bring vulnerability and nuance to their roles.

I don’t think there’s been a misstep in Allison’s or Bradley’s performance. They always make it very specific and unique to who they are as actors. You get that from Allison and Bradley all of the time. It’s annoying, actually, how good they are.

The Diplomat made a lot of straight offers to put the cast together, but in general, when it comes to actor auditions, what are you looking for?

When I see a self-tape, or it’s in person, if you come to me with a point of view and a specific choice, I know that I can work with you. I can give you notes and help shape it because you came with an idea of who you believe this character to be, and that’s exciting to me. But the actors who come in and ask me, “What is it that you want to see?”—they have already lost me. Because they’re not thinking about how they want to play this role. They’re just thinking about how to get the role. And that’s not the same thing.

The Diplomat’s first three seasons are streaming on Netflix.

Featured image: The Diplomat. (L to R) Keri Russell as Kate Wyler, Allison Janney as Grace Penn in episode 303 of The Diplomat. Cr. Courtesy of Netflix © 2025