Season 3 of the Emmy-nominated political thriller The Diplomat is set to premiere on Netflix on October 16, 2025. The streaming service announced the release date along with a new teaser that hints at escalating tensions, power struggles, and personal conflicts at the highest levels of American politics.

The new season picks up in the immediate aftermath of the shocking Season 2 cliffhanger, where Vice President Grace Penn (Allison Janney) unexpectedly ascends to the presidency following the sudden death of President William Rayburn (Michael McKean). The teaser reveals the consequences of the explosive finale are beginning to unravel, with tensions running high among all parties.

With Grace Penn now in the Oval Office, Ambassador Kate Wyler (Keri Russell) faces a challenging new dynamic. As Kate knows about Penn's questionable actions, she warns that "A terribly flawed woman is now the president, and only we know just how flawed". The relationship between the two women is delicate, especially with Kate holding knowledge of Penn's secrets.

The death of the president has reshaped the political landscape, and Grace Penn, portrayed as calculating and enigmatic, finds herself in power. Kate, who had accused Penn of orchestrating a plot while being considered as her successor, now faces a difficult situation.

Hal Wyler (Rufus Sewell) may have inadvertently triggered the chain of events that led to Penn's elevation. Despite the circumstances, Hal continues to push for Kate to become Penn's vice president. Kate steps into a role she never wanted, gaining unexpected freedom and navigating a complicated friendship with Foreign Secretary Austin Dennison (David Gyasi).

A notable addition to the season is Bradley Whitford, who joins the cast as Todd Penn, Grace's husband and the new First Gentleman. This marks a reunion for Whitford and Janney, who starred together in The West Wing. Whitford expressed his excitement about joining the show and working with the cast, including Janney, Russell, and Sewell. Janney also shared her enthusiasm for Whitford's casting, considering it the "best idea ever".

The new season will consist of eight episodes. The Diplomat has already been renewed for a fourth season, indicating its popularity and critical acclaim. Debora Cahn serves as the showrunner and executive producer, along with Keri Russell, Janice Williams, Alex Graves, Peter Noah, and Eli Attie. The cast also includes Ali Ahn, Ato Essandoh, Rory Kinnear, Nana Mensah, and Miguel Sandoval.

Creator Debora Cahn teased that Season 3 "flips the chessboard". The season will explore the evolving bond between Kate and Hal, as well as the dynamic between Kate and the new First Gentleman, Todd Penn.