Netflix's The Diplomat season two finale unveils unexpected mastermind behind bombing

WARNING: This article contains spoilers from The Diplomat.

The Diplomat season two has arrived in full on Netflix but what transpires in the finale of this latest instalment?

Keri Russell returns as US ambassador to the UK, Kate Wyler, who has been engrossed in investigating who orchestrated the bombing of HM Courageous at the conclusion of the first series.

After extensive probing and unforeseen twists, she finally uncovers the truth, which is not what anyone anticipated.

The Diplomat season 2 ending explained

Since the inaugural season, there were strong suggestions that Prime Minister Nicol Trowbridge (portrayed by Rory Kinnear) was responsible for the attack, but this turned out to be 'false'.

It became clear that his close associate Meg Roylin (played by Celia Imrie) was implicated.

To determine if Trowbridge was aware of the incident, a scheme was devised by Kate Wyler (Keri Russell) and Austin Dennison (David Gyasi).

Their plan involved getting both Meg and the Prime Minister in the same room where she would admit her role in the bombing.

She revealed that the plot was executed when it seemed Scotland was about to secede from the union. Following the attack, Trowbridge was expected to demonstrate leadership and reintegrate them.

The intention was not to cause any casualties, but the attack resulted in the death of 43 people. It soon became evident that Trowbridge was oblivious to this as he started to confront Roylin.

However, the orders originated not from Roylin but from Vice President Grace Penn (Allison Janney), who orchestrated everything without President Rayburn's (Michael McKean) knowledge.

Upon discovering that Kate was aware of her actions, Penn justified her decision as a necessary step to bolster British unity and quell Scotland's burgeoning independence movement.

Initially, Kate accepted Penn's rationale but later concluded that Penn should no longer hold power, announcing her ambition to become vice president.

In an attempt to secure the position, Kate enlisted Hal Wyler's (Rufus Sewell) help to inform the secretary of state about Penn's role in the bombing, but he instead chose to confront President Rayburn directly.

It was later revealed, when Hal tried to clarify the situation to Kate, that the president was so distressed by the revelation that he passed away.

Upon learning this, Secret Service agents swiftly surrounded Penn, and it was promptly recognised that she had become the new President of the United States.

The Diplomat is available to watch on Netflix.