Treason ending explained: Who is double agent Dorian?

Those men were locals who were working for Kara. She had guaranteed their safety but in a violent turn of events, they had been captured and tortured in front of their families, before being killed, with Kara hunting the culprit ever since.

Following their deaths, there was an uprising in the city, which forced the British to evacuate. But Adam remained and saved the embassy from falling, which boosted his reputation at MI6. Angelis, however, believed that was part of a plot to help the Russians take control of the region and had kept him close ever since to monitor his movements.

But as the plot thickened, it became abundantly clear that there was another person pulling the strings – and be warned: there are spoilers ahead.

Treason ending explained: Who is Dorian?

Patrick Hamilton, Adam's longtime friend and head of MI6's Russia desk, is the traitor.

Their relationship stretches back years, which Paddy attempts to use to his advantage when Adam refuses to tell him why he's meeting with Melnikov, who's attempting to manoeuvre MP Robert Kirby into No 10 so that he can "flip him to the Kremlin".

"Not even me? After 20 years of friendship," he says. "I'm the only one in the building trying to help you navigate this s**t."

In the finale, he attempts to seize Angelis's top secret extortion files from Maddy, which the Russian authorities would use to influence law and order in the UK. But he's no match for her and she successfully passes the information on to home secretary Audrey Gratz. He's later poisoned by Kara, who was seeking revenge for what had happened in Baku.

But the show was also keen to highlight that Angelis was every bit as monstrous as Patrick.

He knew that Kirby winning the leadership race would be a win for Russia, and yet he refused to obstruct any chance of that happening to suit his own agenda: to be the longest-serving and most powerful chief in UK history.

"This country has forgotten how much it needs us," he says of MI6 and his colleagues. Angelis wanted Kirby to secure his position as prime minister so that he could swoop in and expose him, in turn strengthening the security service's influence and power.

But during a committee hearing, Audrey lifts the lid on Angelis's blackmail racket and clears Adam's name: "Far from being a traitor, I believe he lost his life rooting out treachery at the heart of the establishment."

Adam's wife Maddy also vows to expose CIA operative Dede Alexander for her role in the saga. The US operative had orchestrated the kidnapping of Adam and Maddy's daughter Ella to draw him out of the shadows.

As for Kara, she will return to Russia. "Will you be safe?" asks Maddy, concerned for her welfare.

"It's my home," she responds, with the pair sharing one final hug before going their separate ways.

Treason is streaming now on Netflix. Sign up for Netflix from £6.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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