Near-future cyber-thriller The Undeclared War has released a fast-paced trailer for its second season, introducing Blue Lights' Siân Brooke's new character as the GCHQ faces a "nuclear piece of malware" and a mole weakening them from the inside.
Created by Peter Kosminsky, The Undeclared War season 1 followed Saara Parvin (Hannah Khalique-Brown), a student doing a work placement at the Government Communications Headquarters (GCHQ), where she finds herself involved in a cyber attack.
Now returning with "a fresh wave of tension and drama" as teased in the synopsis, the series sees the elite Malware Department at GCHQ grapple with a new menace.
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Saara and her boss Danny Patrick, played by Mission Impossible's Simon Pegg, are called to face a devastating threat. In the trailer, Danny states that they're up against a "potentially nuclear piece of malware", as new Foreign Secretary Richard Marston (Ed Stoppard) says that it "constitutes the cyber equivalent of an armed attack on the United Kingdom".
Siân Brooke joins the cast of season 2 as Danny's wife Barbara, an ex-MI6 agent who now works as an analyst at GCHQ. As Danny and Saara are convinced that the agency has a mole, Barbara and a new character played by Jason Tobin agree that everything they seem to be telling her people, they already know.
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With the show also welcoming Dept Q star Chloe Pirrie as Lt Colonel Roz Cavendish and Black Panther's Danny Sapani as Charlie Francis, GCHQ's Head of Security and Danny's childhood friend, loyalties are tested when fingers are pointed to flush out the mole.
"These are very serious allegations you're making here about a senior and widely respected colleague," Charlie says when he's informed about the potential traitor. But who's the suspected mole and who's levelling the accusations?
"I want to thank Channel 4 and Universal Global Television for all their support, and I am delighted to welcome back Simon Pegg and thrilled that he will be joined this season by the wonderful Siân Brooke," Colin Callender, series co-creator and executive producer, said in February 2025 when the series was renewed.
"As we dive into the second season of The Undeclared War, the series raises the stakes as it explores the ever-increasing complexities of a world where technology and humanity collide."
"With gripping new threats, unexpected twists and a fantastic mix of new and returning characters, this next chapter of The Undeclared War promises to be an exhilarating ride," Kelsey Balance, EVP of Global Scripted Series at Universal Gloval Television, also said in a statement.
"Together with our partners at Playground and Stonehenge Films, we look forward to returning to the high-stakes and ever-changing world of cyber warfare for audiences to explore once more."
The Undeclared War season 2 will air and stream on Channel 4.
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Reporter, Digital Spy
Stefania is a freelance writer specialising in TV and movies. After graduating from City University, London, she covered LGBTQ+ news and pursued a career in entertainment journalism, with her work appearing in outlets including Little White Lies, The Skinny, Radio Times and Digital Spy.
Her beats are horror films and period dramas, especially if fronted by queer women. She can argue why Scream is the best slasher in four languages (and a half).
