Treason premieres all five episodes on December 26, 2026 on Netflix.
Synopsis
Trained and groomed by MI6, Adam Lawrence’s career seems set. But when the past catches up with him in the form of Kara, a Russian spy with whom he shares a complicated past, he is forced to question everything and everyone in his life. A triangular relationship forms between Kara, Adam and his wife, Maddy; three people who are trying to expose each other’s secrets, navigate political and diplomatic relationships, whilst hanging onto their personal lives, and those they love most.
Review
Picture it: the leftover turkey has grown dry and the family are arguing over what’s next on the Christmas watch list. In amongst all of the re-runs and Christmas specials is Treason, a brand new British spy thriller from the Oscar-nominated Matt Charman (Bridge of Spies).Not only that but the series has Marvel’s Man without Fear, Charlie Cox in the starring role.
Treason is a hugely twisty mix of classic British espionage which folds in some American sensibilities in its storytelling. It’s fair to say that us stuffy Brits like a sizzling mystery but rarely outside of James Bond do we truly get down to the fisticuffs. With Treason, Charman tries his level best to roll up our sleeves and bring a new level of action with compromising on any of the complex and twisty plotting.
It all starts when the head of MI6, Sir Martin Angelis (Ciaran Hinds), is poisoned whilst supping a cool whiskey at his gentleman’s club. His hospitalisation triggers the immediate promotion of Adam Lawrence (Cox) in to the role of C. We meet Adam as his gives a talk at his son’s school, explaining that the term M is something purely for the movies. The simple scene establishes two incredibly strong plot lines for the series. One: that we’re about to learn a lot about the structure of MI6 and two, that Adam Lawrence is a devoted family man.
Across five episodes, Treason manages to pull off an incredibly complex plot. There are several key players in London alongside MI6. There’s Tracy Ifeachor as Dede, a CIA agent working to uncover a mole within the British agency, and Kara (Olga Kurylenko) a former-Russian agent with ties to Adam’s past. Taking in to account the excellent Oona Chaplin as Larwrence’s wife, Maddy who also happened to serve some time in the military with Dede.
The trio of women are really at the centre of the action, perhaps more so than Adam. Whilst he is the key figure connecting them, it’s their movements and machinations which keep the plot hurtling forwards across the season.
Kurylenko could easily continue on from Treason in her own series. Kara is a complex and incredibly well realised character. There are strong hints throughout the season that Kara has a tragic history, a history which informs her dedication to uncover the mystery behind a series of killings during a mission in Baku.
The level of agency afforded to Charman’s female characters is outstanding. Spy fare is so often either lead by a male or female lead. James Bond being a prime example of a strong British franchise, but one where the women are relegated to love interests. Looking to the us there are series like Alias where Jennifer Garner’s Sydney Bristow is the undisputed lead and the men play supporting roles. That is not the case with Treason. The sexes are truly equal in their devotion to uncovering the truth.
Despite the complexity, Treason isn’t difficult to follow. The dialogue is well balanced between the necessary exposition and espionage posturing. There are plenty of opportunities for various characters to explore the twists of the plot, leaving us to follow the breadcrumbs to form our own conclusions. Happily, the ending isn’t entirely predictable. Several 11th hour twists perfectly serve to keep the audience on the edge of their seats as Martin Angelis’ castle comes crumbling down around him.
The experiment to mix the sensibilities of both UK and US spy thriller’s is mostly successful. The series does have a more dramatic sense of pacing but somehow still remains very measured. The pace continually picks up across the first four episodes and finds Treason absolutely hurtling in to its fifth and final outing. I had anticipated a little more hand-to-hand combat in the style of US series. If you’re looking for more of that shoot first, ask questions later sensibility of our American cousins then Treason may not be the show for you. It utilises the action when necessary rather than choosing to pit characters against each other for the sake of it.
It does feel like Treason is building towards a potentially larger story in a second season. I would, in fact, gladly tune in to see what happens next for the surviving characters. But with Treason pitched as a limited-series it does feel a little like a more conclusive ending could have helped it stick the landing.
Verdict
Treason is a taut spy thriller which mixes the best of cerebral British political intrigue with a dash of American high stakes drama. Cox is fantastic but the trio of Kurylenko, Chaplin and Ifeachor are a force to be reckoned with.
⭐⭐⭐⭐
