The Undeclared War, Channel 4 review — secret service thriller stars Mark Rylance and Simon Pegg

Things, it seems, could always get worse. Set in April 2024, Channel 4’s new alternate-future drama finds Britain in an even more unstable situation than today. The economy is in recession, Covid still lingers and a mysterious cyber attack has taken most of the country offline. As he vows to get things under control, the deeply unpopular prime minister is loudly heckled. Could you imagine!

He is Andrew Makinde (Adrian Lester), a serious and solemn man who, it transpires, succeeded in a coup against Boris Johnson. With a general election just around the corner and the Conservatives trailing Labour in the polls, the new PM demands options for a robust retaliatory response against the cyber attack’s assumed culprit: Russia.

So begins The Undeclared War, a six-part series created by Wolf Hall director Peter Kosminsky, which is evidently eager to root its bleak imaginings in a background of real-world politics, institutions and figures. A meeting about the potential fallout of targeting Vladimir Putin can’t help but elicit a cold sweat.

There’s not much else in the opening two episodes that feels gripping or particularly authentic. We hear about the attack, for instance, but don’t get a sense of the chaos, nor enough insight into the goings-on in government and diplomatic circles. Instead, by basing the majority of the action in intelligence agency GCHQ, the show takes on the air of a more generic secret service thriller.

The focus there is on work-experience recruit Saara (Hannah Khalique-Brown), whose first day in the malware department — led by Simon Pegg’s Danny Patrick — coincides with the cyber attack. Most interns would still be getting acquainted with the coffee machine but this pushy student insists on helping dismantle the virus. Combing through endless lines of code (the show finds a smart way of visualising this tedious process), her keen eye catches an additional, overlooked threat. A further catastrophe is averted for now.

Saara’s discovery puts her in an invidious position with her bitter line managers, who stifle her when she asks to take on more responsibility. Eventually she turns to other GCHQ pariahs: the little-trusted NSA envoy Kathy (Maisie Richardson-Sellers) and avuncular old-timer John. He’s played by Mark Rylance, who, like the other top-billed names, is kept on the periphery for now. While the PM is cautioned to proceed with restraint, we must hope the show itself doesn’t follow that advice.

★★★☆☆

On Channel 4 and All4 from June 30 at 9pm; new episodes air weekly

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