The Ending of 'The Diplomat' Season 2, Explained: Breaking Down Who Planned the Attack and the Shocking Death

Season 2 of Netflix's political thriller The Diplomat begins with a bang—literally. Created by The West Wing alum Debora Cahn and starring Keri Russell, the series follows the titular diplomat Kate Wyler (Russell) as she's appointed ambassador to the United Kingdom, following the mysterious bombing of a British warship. Throughout the first season, Wyler works with the British Foreign Secretary (and several other members of The Diplomat's talented cast) to figure out who bombed the ship, while avoiding a possible World War 3. Meanwhile, the U.S. President also has an ulterior motive for Kate's appointment: to see if she's a good choice to become the new Vice President.

After a packed (although truncated) season, The Diplomat season 2 ends with a cliffhanger that changes the entire series' dynamic, ahead of a (thankfully) already-renewed season 3. Below, read on for a breakdown of the complicated ending of The Diplomat season 2.

Did Prime Minister Trowbridge plan the ship explosion on 'The Diplomat?'

By the end of The Diplomat's first season, Kate has a prime suspect for the bombing: Nicol Trowbridge (Rory Kinnear), the U.K.'s Prime Minister. The theory is that the British leader ordered a false-flag attack on his own ship, the HMS Courageous, and framed Russia to bring the country together, as Scotland's possible secession threatens his legacy. All the signs still point to Trowbridge for most of season 2: The car bomb that went off at the end of season 1 killed British MP Merritt Grove (Simon Chandler), who was (presumably) about to reveal the ship-bombing plot to Kate's husband Hal Wyler (Rufus Sewell). It also killed Kate's employee, Ronnie Buckhurst (Jess Chanliau), and gravelly injured both Hall and Kate's deputy chief Stuart Hayford (Ato Essandoh). Soon after, Roman Lenkov (Sam Douglas), the Russian mercenary who bombed the ship, is killed before he can spill on who hired him.

Kate and co. have one major win: Margaret Roylin (Celia Imrie), Trowbridge's longtime advisor, who comes to Kate seeking refuge. She knows the truth of the plot, the full extent of which she will only reveal to Hal. The story she tells Kate: Roylin, Grove, and an over-eager accomplice called Stendig hired Lenkov to attack the Courageous, to unite the U.K. and stop the threat of Scotland's secession, and Trowbridge had no idea. She's clearly hiding some extra details from Kate and CIA spy Eidra Park (Ali Ahn), but Hal completely believes her.

So, Kate and Eidra decide to get Roylin and Trowbridge in a room together and monitor how he responds to see whether or not the prime minister is in on it. (They also loop in Dennison, who doesn't have much to do this season.) Trowbridge responds to Roylin's confession by snapping, strangling Roylin in a blind rage, and knocking her to the ground so hard her head starts bleeding. If that response and his subsequent shock are faked, Trowbridge missed his calling by not going to RADA instead of Oxbridge. So, as it turns out, Trowbridge is innocent.

Did Vice President Grace Penn plan the ship explosion on 'The Diplomat'?

After the season's first climax of Trowbridge maiming Roylin, The Diplomat brings in a heavy hitter in the fallout: U.S. Vice President Grace Penn, played by Allison Janney. Her visit is explained as half support mission for the whole accused-the-prime-minister-of-a-false-flag-attack cleanup, and half to finally get a look at the woman who's being set up to take her job. Grace deftly handles Trowbridge and Dennison, feeding them the decision to bury the fact that British citizens coordinated a terrorist attack against their own country, and Kate's so impressed she convinces Grace to fight to keep her job. It seems like all of the show's central conflicts have been solved by the end of season 2, episode 5; The Courageous plot is wrapped up, and Kate won't need to become VP. Until Hal reveals the big twist: Roylin and co. may have hired Lenkov, but the plan to bomb the Courageous came from Grace herself.

So, the Vice President of the United States planned a minor (at least it was supposed to be) false-flag attack on a British warship. The Prime Minister has no idea; the President has no idea. We don't know why Grace committed a war crime at the start of the season 2 finale, but later, we hear the explanation from Grace herself. In the side room of an opulent British mansion, she draws out America and Russia's arctic military positions on a world map, like she's a football coach ahead of a game. Russia has a wide-open route through the Arctic and North Atlantic where a sub could go straight for N.Y.C.; the only place where the U.S. could detect a Russian sub along the way is Creegan, a Scottish submarine base that holds all of the U.K.'s nuclear weaponry. (If you were wondering, Creegan is a real-life base!) However, as Grace says, "The Scots hate nukes, and they hate English overreach, but they really hate having a bullseye on their heads."

According to Grace (and Kate agrees), if Scotland seceded from the U.K., they'd immediately close the base and Russia would likely escalate their military activity, as they did when the U.S. removed their military presence in the past. Grace knew there was no way they could lose Creegan, so she went to Roylin. There weren't supposed to be any casualties in the attack, and Grace lives with the responsibility for the 43 deaths that came from her decision. Penn owns the toll and counts it as the cost of protecting "40,000 or 40 million" from a possible nuclear war.

Does Kate Wyler want to be vice president on 'The Diplomat?'

As proven by seasons 1 and 2, Kate is not interested in becoming Veep, even though the table has been set for her. Before the events of season 1, the White House discovered that Grace's husband was guilty of slight financial fraud; it still hasn't gotten out by the end of season 2, but it's been assumed that Grace would step down as soon as it got out. This gives President William Rayburn (Michael McKean) the chance to appoint someone to the office, without them needing to campaign. Someone like Kate, deeply competent at her job but completely repulsed by the spotlight, can govern without an election. WH Chief of Staff Billie Appiah (Nana Mensah) summed up the thought of putting Kate in charge of foreign policy quite poetically in season 1: "Can you imagine hiring someone for a key government position just because you think they'd be good at it?"

There are many reasons Kate is averse to the idea of becoming VP. She already hates the flashier duties of her job as a British ambassador, so it's hard to imagine her on even more of a stage. Hal and his tendency to scheme in favor of his own agenda is also a large part of it. They were headed toward divorce before the VP spot became available, but once he found out that the Second Gentleman role was possibly in his future, he changed course... without initially telling her, of course. However, by the end of the second season, it seems they've learned how to work together amicably again, though it isn't clear if Hal is actually trying or slowing down amid his recovery. The final moments of season 2 show that the latter may be a serious possibility.

By the start of the season 2 finale, the revelation of Grace's involvement in the Courageous attack has changed everything, and Kate finally begins to accept the idea of herself as the VP who can step in after Grace has crossed such a big line. She even tells Stuart she's interested, and he immediately starts cleaning up her image—no more dark suits! hair up in a neat bun!—so she exudes her inner competence on the outside. While this is happening, Trowbridge is in Number 10 feeling guilty that he doesn't want to step down for completely missing the terrorist plot in his own government, so he recommends Grace to become the U.S. nuclear czar and lead defensive strategy in that area. This would mean Grace stays as vice president—and solidifies her decision to fight for her job once her husband's scandal comes out.

Grace kindly tells Kate about the recommendation, while Stuart goes to Billie about it. Billie insists that she will squash it—and is very adamant that Grace needs to go—if Stuart can keep Trowbridge from mentioning it in his speech at a dinner. Stuart succeeds, but this, in addition to the makeover is how Grace knows that Kate's actively going after the VP slot. The entire czar debacle leads Grace to explain Creegan's importance, a.k.a. a great example of why Grace would be a great nuclear czar and Kate may be out of her depth.

That night, Kate and Hal have a heated discussion. Kate recognizes that Grace made a tough call in a horrible situation, and says that Grace "shouldn't be punished for making a decision that had to be made." She admits that ensuring Trowbridge buried it was unfavorable, but she was arguably cutting all loose ends so peace could continue. So Kate prematurely steps down again, but Hal isn't ready to let go of her wanting to be VP. Hal suggests informing Secretary of State Ganon (Miguel Sandoval) and letting the justice system do what it must in terms of Grace's war crimes.

Kate understands that this is half Hal's ambition, but also recognizes her duty to brief her boss on the cause of the Courageous attack. It's not a completely good or selfish decision to snitch on Grace to Ganon (but no decision on this show is black-and-white). So by morning, Kate decides they should tell Ganon, but Hal should be the one to do so since she "needs a clean profile." She tells Hal, "I want to be Vice President."

Is Kate Wyler going to become Vice President in 'The Diplomat?'

The final scene of The Diplomat season 2 is a showdown between Kate Wyler and Grace Penn. Grace asks Kate to ensure she isn't going to tell anyone the full truth of the Courageous attack; Kate insists that she won't. Grace then tells Kate to stand down and stop chasing her position, and when Kate assures she isn't, Grace asks why Kate's hair is still up in the aspiring VP bun. Kate says that if the president asks her to take office, her answer is yes, but Grace responds that when it's clear that Kate's out of her depth and the president is just anxious, then Kate's answer should be no. Grace asks why Kate thinks she should take over as VP, but before Kate can answer, Stuart pulls her for a call from Hal.

As it turns out, Hal got dressed and went to the C.I.A. office, prepared to support Kate and tell Ganon; to be fair, he has been a good boy all season. But at the last second, he decides not to call Ganon, but President Rayburn himself. The next thing we see is Hal terrified and frantic to talk to Kate. While Kate was making Vice President Penn an enemy, President Rayburn was so upset with Hal's news that he had a heart attack. The president is dead, and an army of Secret Service runs across Kate's lawn to get the new President, Grace Penn.

So, where we are at the end of The Diplomat season 2: Grace Penn is President. Grace is very pissed at Kate Wyler. Kate is still the Ambassador to Britain, but Foreign Secretary Dennison has cut ties with her, and Prime Minister Trowbridge is pissed at her, too. Kate and Hal are on good terms, but who knows if that lasted through that phone call.

Also, Stuart and Eidra are still broken up, probably for the best since he keeps making her cry at work even after she told him to stop making her cry at work.

Most importantly, there's now a VP seat up for grabs, and Grace Penn's responsible for filing it. No one knows how it'll be filled in The Diplomat season 3... except creator Debora Cahn, who dropped an interesting hint while speaking with Tudum. "Season 3 flips the chessboard," she told the outlet. "In Season 3, Kate lives the particular nightmare that is getting what you want."