🤐 SPOILER ALERT 🤐 

Keri Russell is calling in a code red. 

Episode 8 of The Diplomat delivers a showstopper fashion moment that might actually be more jaw-dropping than the finale’s big twist. After being pushed to the brink by her powder keg of a husband Hal (Rufus Sewell), ambassador Kate Wyler (Russell) is ready to finally shine in her own right. “When you put on a red dress, you mean it. You know?” Russell tells Tudum.

Kate’s moment in the limelight is certainly the stuff of Cinderella fantasies. After all, the romantic backdrop is the Louvre in Paris, and the dashing UK foreign secretary Austin Dennison (David Gyasi) is ready to take her arm.

Alex Bailey/Netflix

We see the result of Kate’s transformation not only in her walk, demeanor and updo, but in Dennison’s eyes as he watches her descend the grand staircase of the museum. “Be cool. You got this,” Gyasi recalls thinking to himself when he first saw Russell in her full red dress glory. “And if you haven’t, Dennison’s got this.”

The long train of her dress was intentional, so that Dennison could help escort Kate down the stairs to the gala event and play up their sexual tension, says costume designer Roland Sanchez. “It was a romantic moment for Dennison to see her and be wowed by this version of her, after all their back-and-forth,” he adds.

Kate’s signature color has been black all season, so her choice of a bold red is a major statement. “This character likes to not be noticed too much,” says Russell. “She likes to wear black forever, and blend in.” But after Hal breaks her trust yet again, she’s saying “I’m taking this one for me,” and putting her usual black dress — and complicated marriage — back into her suitcase for now.

Showrunner Debora Cahn wanted the red dress to symbolize a real departure for Kate, especially after she was so adamant against doing anything with Cinderella undertones at the start of the season. “She’s very clear in the first episode; she’s got a black suit and another black suit,” Cahn tells Tudum. “She’s worked in places where you’ve got to both look good and be able to run at the same time, because the bombs [could] drop out of the sky.” 

Sanchez echoes that the switch-up in the finale demonstrates Kate’s major progression as a character after a season of wearing “subdued” Vince silk blouses and Theory black suits. Kate has realized that she needs to get out of her comfort zone –– wearing the red dress is a necessity rather than a luxury for her going forward. “You can see her awakening [and understanding] what she needs to do, to get to where she’s got to be as a diplomat and as someone being groomed for the vice presidency,” says Sanchez. “That red dress is what she needs for that power moment.”

Alex Bailey/Netflix

Kate’s decision symbolizes her letting go of her past positions and shedding old skin. She’s allowing herself be something that she’s previously held a lot of prejudices about, being “frivolous or impractical or inappropriate,” Cahn explains. But now, “She’s choosing to step out of that person she’s been for such a long time and open the door to something different. Open the door to a different life, relationship, who knows?”

The red dress itself was scripted by Cahn, and Russell tried on four or five different gowns until they found the perfect fit. “Keri’s a dream to dress, so it’s not hard to make her look beautiful,” says Sanchez.

To create Kate’s one of a kind look, the costume department re-created a design from Galvan London. “They had made this dress and it was stunning. We used it as a base, but we needed it to be more dramatic,” says Sanchez. “We retooled and re-created parts of it, made the train quite a bit longer and changed the neckline a bit.” 

Sanchez and his team were also adamant about changing the original burgundy of the Galvan London dress to a more standout red fabric, so it wouldn’t blend in with the wine-colored walls of the Louvre museum where Kate speaks with the French diplomat Brielle Fournier. And if you didn’t notice the first go-around, give Kate’s grand entrance scene another rewatch — everyone else at the gala, aside from Kate, is purposefully wearing dark colors. “It was 100% intentional for her to stand out in that whole setting,” says Sanchez.

While it’s a big move for her character to suddenly don a red dress, Russell has a long history of wearing striking and head-turning looks. Think back to her Felicity days and the time she wore a red dress to a dorm party to make Scott Speedman’s Ben jealous in Season 2.

“I forgot about that! I totally forgot about that. I remember the red dress, oh my word,” says Russell. “Well, a girl’s got to have a red dress!” 

The Diplomat is now streaming on Netflix.

Additional reporting by Cole Delbyck.