The Diplomat renewed for Season 4; here’s Season 3's ending explained

The American political thriller The Diplomat, starring Keri Russell and Rufus Sewell in the lead, returned for its third season with an 8-episode drop on October 16 on Netflix. The show ended with an explosive revelation involving a nuclear weapon and that it had been renewed for another season. If the timeline of Season 3’s arrival is anything to go, fans of The Diplomat can expect Season 4 to return in October 2026.

Here's what played out on The Diplomat Season 3

The critically-acclaimed show, created by Deborah Cahn, centres on US ambassador to the UK, Kate Wyler (Russell), who, at the end of Season 2 was gunning for the post of US Vice President, after she uncovered a ‘terrorist plot’ that the sitting VP, Grace Penn (Allison Janney) had orchestrated in the UK.

But then, everything goes topsy-turvy, when Kate’s career diplomat hubby Hal (Sewell), informs the President about his wayward VP, only to have the Commander-in-Chief keel over and die, while still on the phone with him. Season 3 picked up from this exact moment, with Grace going from VP to President in the blink of an eye and Hal and Kate still trying to convince her that the latter should now be her VP.

In one of the season’s first major twists, Grace declares she wants Hal, and not Kate, with her in the White House. Instead of abandoning her post in the UK, Kate continues to serve as ambassador, while also fulfilling her duties as Second Lady as and when a requirement arose. When it then comes to light that the Russians may know of the US government’s involvement in the bombing of the HM Courageous that took 41 lives, it is decided that the President will come clean with UK Prime Minister Nicol Trowbridge (Rory Kinnear), albeit with a slightly different version of events.

Also read: Newsletter | The Diplomat: You Won't Get Wholly Attaché-d To Keri Russell's Netflix Drama

Grace tells Nicol that the US was involved, at the behest of the late President Rayburn, for whom, the UK President’s long-term advisor, Margaret Roylin (Celia Imrie), carries out the attack. After agreeing to announce this to the world in a manner that does not harm either side, Nicol squarely blames the US and is then forced to seek Chinese help when a Russian submarine ends up in UK waters.

Turns out, the missing Russian sub is carrying a nuclear weapon that the rest of the world believed they were far off from creating. But the Russians had cracked it and now, it could land in the hands of the Chinese, following the stand-off between the US and the UK. Kate and Hal figure out how to get the UK to play ball again – Grace would apologize and then offer to help them take care of the nuke.

But then, shortly after the US President shows Nicol images of the nuke, the weapon goes missing and that is when Kate realizes that Grace and Hal sneaky plot involved more than just taking pictures. They’d stolen the nuke. What will Kate do with this information as she prepares to head back to Washington as Second Lady? This and more will unfold when The Diplomat returns in 2026 with Season 4.

FAQs

Q. Will there be a season 4 for The Diplomat?

A. Yes. The Diplomat has already been renewed for a fourth season. It is expected in October 2026.

Q. Where to watch Season 3 of The Diplomat and how many episodes does the season have?

A. Season 3 dropped on Netflix on October 16. It has 8 episodes like Season 1.