The Diplomat season 2 ending explained: What just happened?

The first season ended with both a literal bang and a bombshell reveal, yet somehow this season gives it a run for its money, with an explosive final moment that has left the fates of Kate and Hal up in the air.

Wondering how things ultimately conclude in season 2 and how it paves the way for season 3, which has officially been given the green light.

Read on for everything you need to know about the ending of The Diplomat season 2, including who ordered the HMS Courageous bombing and what happened to Kate, Grace and President Rayburn.

Rory Kinnear in The Diplomat. Netflix

Despite the ending to season 1 seeming to suggest that ritish Prime Minister Nicol Trowbridge (Rory Kinnear) was behind the attack, The Diplomat season 2 saw Keri Russell's Kate and David Gyasi's Austin looking into it, and finding that he actually had no involvement whatsoever.

While they believed he was behind the bombing, Austin led an attempt to get rid of Trowbridge, but it failed as his popularity began to soar.

One person who was definitely involved was Meg Roylin, the Conservative Party operative and ally of Trowbridge. To confirm that she was telling the truth about Trowbridge's innocence, Kate got the two of them in a room together, and got her to confess the truth to him.

She told him that she had seen Scotland was going to leave the union, but knew if she told Trowbridge he would have only pushed them further away.

To stop this, she had brought together a team to put in place a plan to attack HMS Courageous. They hired Roman Lenkov to do so, giving Trowbridge an opportunity to show leadership, and bring Scotland back into the fold.

There were not supposed to be any casualties, but the plan went awry and 43 people were killed.

Upon hearing this, he reacted with blind rage, throttling Roylin. This visceral reaction confirmed that he really didn't know anything about it.

Keri Russell and Rufus Sewell in The Diplomat. Netflix

Instead, it turned out that the while plan may have involved a number of people, including Roylin and Conservative MP Merrit Grove, it was concocted by someone even higher up - Vice President Grace Penn.

She did this without President Rayburn becoming aware, and flew to London in order to ensure Trowbridge covered up what he had found out.

Once Grace became aware Kate knew, she took her aside to explain her decision-making. She explained the Russia's nuclear proliferation left America under threat, and that all of the UK's nuclear weaponry was housed at Creagan, a base in Scotland, which was also the only nuclear base in Europe where the US could dock their own submarines.

Grace said this was the last place the US could detect Russia sending a nuclear submarine before it was headed to New York. She said that if Scotland had gone independent, they would have closed the base, due to their national hatred of nuclear weapons and their adversity to having become a target in the modern theatre of war.

At first, Kate was won over by her logic, believing Grace had made a difficult but crucial decision. However, she later changed her mind and decided she wanted to be vice president.

Michael McKean as President William Rayburn in The Diplomat. Alex Bailey/Netflix

Towards the end of the season, Grace decided she would stay on as vice president after all, when offered the position of nuclear tsar. She was offered this position after Trowbridge convinced President Rayburn she should be given the job.

However, given everything she knew, Kate had misgivings. She also decided she wanted the top job, and to help this along, had Hal call the secretary of state to inform him of Grace's involvement in the HMS Courageous bombing.

Hal changed the plan at the last minute, and instead decided to speak directly to President Rayburn. Hal later relayed the conversation he had in a hurried, frantic tone to Kate over the phone, just after she had revealed her true colours to Grace, and told her she wanted the job for herself.

Hal revealed that he disclosed all of the information to Rayburn, and that it made him upset - really upset. In fact, he was so upset that he died!

As she received this information, Kate watched as Grace was surrounded by Secret Service operatives. It became clear - upon the event of Rayburn's death, Grace Penn had become president of the United States of America. Uh oh...

The Diplomat season 2 is available to stream in full on Netflix now – sign up from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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