Channel 4 Returns to 'The Undeclared War'

It took most U.K. broadcast networks a little longer than was probably good for them to hop aboard the streaming service bandwagon, but since the end of 2022 and the launch of ITVX, the primary networks have all started focusing on making series for broadcast designed to boost streaming viewership numbers. Channel 4 has probably suffered more than most, despite being one of the earliest adopters of the move to streaming. (Like HBO, it just reconfigured its existing on-demand service in 2016.) Between threats of being sold off by the Tories and being mired in third place behind the iPlayer Player& ITVX, the network has struggled to stay afloat.

But it's a new day since Labour took the reigns in July 2024. While most of the focus has been on the BBC's upcoming charter renewal, Channel 4's Drama director, Ollie Madden (who is also in charge of Film4), announced he was aiming to double Channel 4’s commissions to achieve having new series premiering year-round; considered a key pillar in the network’s move to becoming streaming-first.  While most of the 2025 series Madden announced are new works (which we will run down in another post), one title did get a second season re-up as part of the network's expanded offerings: 2022's British spy series The Undeclared War, which streamed its first season on Peacock in the states.

Like most of its British thrillers, The Undeclared War was mostly overlooked on Peacock when it debuted. However, unlike The Capture, this wasn't about a show being lost in the shuffle as it transferred across the pond. The Undeclared War's first season merely did ok in the U.K. as well, which might explain some of the casting changes heading into Season 2.

Here's the show's second-season synopsis: 

Set in 2024, The Undeclared War returns with a fresh wave of tension and drama as the UK’s GCHQ grapples with the aftermath of a devastating Russian cyber-attack. Just when it seems the UK has gained the upper hand, the team uncovers a far more dangerous threat.

Fans of the show's first season will note a fun twist to the series' original timeline setting; when Season 1 was broadcast in early 2022, it was set in "the near future" of 2024. Season 2 will pick up directly following the events of the first season, still in 2024, which, by the time the series makes it to broadcast later in 2025 (and then across the pond, by which time it might be 2026), will place the events of the second season having occurred in the recent past.

Season 1 stars Simon Pegg (Star Trek) returns as Danny Patrick, Director of Operations at GCHQ, and Hannah Khalique-Brown (Black Doves) as Saara Parvin, the coder still on placement at GCHQ. Other Season 1 returnees include Alex Jennings (The Crown) as Danny’s boss, GCHQ Director David Neal, and Ed Stoppard (Home Fires) as newly elevated Foreign Secretary Richard Marston.

Newcomers to the series include Siân Brooke (Blue Lights) as Danny's ex-wife, Barbara Patrick, now a GCHQ analyst; Danny Sapani (The Diplomat) as Charlie Francis, GCHQ’s Head of Security; Chloe Pirrie (War & Peace) will play Lt Colonel Roz Cavendish, seconded by Marston to GCHQ in the newly created role of Director of Rapid Response; and German Segal (Wolf Hall) as Russian coder Vadim Trusov.

Writer Colin Teevan (Das Boot) and director Paul McGuigan (Sherlock) return for the show's second season, with Teevan once again penning all six installments, McGuigan helming, and Caroline Levy producing. Teevan and McGuigan executive produce with series co-creators Stonehenge Films' Peter Kosminsky and Colin Callender, the latter of whom produces for Playground alongside Daniel Gratton and Noëlette Buckley.

The Undeclared War Season 2 is expected to debut on Channel 4 in the U.K. sometime in 2025 and will most likely wind up lost in the bowels of American streaming service Peacock when it crosses the pond in late 2025 or early 2026.