Keri Russell‘s American ambassador to the U.K. and her vice president husband, played by Rufus Sewell, are trying to navigate a number of strained relationships in the upcoming fourth season of Netflix‘s The Diplomat, the first teaser for which was released Monday morning.

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Season four of the political thriller, consisting of eight one-hour episodes, is set to begin streaming on Netflix on Oct. 15.

The teaser finds Kate (Russell) and Hal Wyler (Sewell) working to repair their frayed relationship after the two reconciled, despite spending much of season three in a private divorce, in the season three finale.

“I’m not trying to get out of the marriage; I’m trying to get back in,” Kate is heard saying as the trailer opens.

She’s then shown taking stock of her and Hal’s dynamic: “We do high highs and really low lows. The fights are going to be spicy.”

And Hal suggests he wants things to be different this time: “You can’t keep doing this to me.”

The two are later shown in what looks like a church where Kate is delivering traditional wedding vows, but specifically pledging to stand by Hal for “worse and worse and worse.”

Hal then asks, “Are you sure?”

The teaser also features rapid-fire images of Kate and Hal rolling around in bed, a glimpse of Kate’s former paramour Callum (Aidan Turner) from when she and Hal were separated and Bradley Whitford‘s first gentleman screaming underwater, indicating that his frustrations at being left out, which turned into jealousy in the season three finale, will continue in the next season.

Indeed, Netflix teases the upcoming season as “two marriages threaten to eat each other alive.”

The synopsis goes on to tease dramatic domestic and international affairs, as it was revealed in the closing moments of season three that Hal and President Grace Penn (Allison Janney) had schemed to steal a Russian nuclear weapon.

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“One catastrophic moment shatters the fragile peace Kate Wyler brokered between the US and UK, as well as the crumbling marriage she’s trying to save,” the synopsis reads. “While she fights to stem the bleeding, President Grace Penn and VP Hal Wyler’s conspiracy to steal Russia’s most powerful weapon hurtles the United States toward war. Kate and Todd, at best an uneasy pair, unite to stop the Grace-Hal alliance from upending the balance of power abroad and at home.”

Speaking to The Hollywood Reporter in May, as The Diplomat was filming its fourth season in Italy (they also shot scenes in New York and the U.K.), showrunner Debora Cahn and the cast promised more interactions between the Penns and the Wylers, including one in Florence with both couples.

Janney and Cahn also teased ongoing fallout from the carrier ship attack that kicked off the series.

“There was always a very long plan for what the carrier meant to the relationship between these two countries,” Cahn explained. “The consequences reverberate through the third season and will continue through the fourth. It’s satisfying for me to be able to make one geopolitical error resonate over a number of seasons. Look at the relationships between countries. We are still dealing with things that happened decades, sometimes centuries ago. Certainly with the U.K., the origin story [of the U.S.] will always be hanging over the way that we interact now.”

Janney adds, “Grace is not afraid to make bold decisions and to suffer the consequences, whatever they are, and she’ll stand behind what decision she makes. Not everyone agrees with her.”

Cahn also shared that while four seasons is a relatively long run in the streaming era, she’s not yet nearing the end of this tale.

“I grew up in broadcast television, where one season was 22, sometimes 25, episodes, so it feels like we’re just getting started,” she said. “It doesn’t feel to me like we’re in season four. It feels like we’re in the juicy middle.”

The cast of The Diplomat also includes Ato Essandoh, Ali Ahn, Nana Mensah and Rory Kinnear. Cahn and Russell executive produce with Janice Williams, Alex Graves, Peter Noah and Eli Attie.

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See first-look images from The Diplomat season four below.