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The Undeclared War

Latest episode

S2 E6

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About The Undeclared War

The Undeclared War is a sci-fi & fantasy and drama TV series that premiered on Channel 4 on June 30, 2022. It has 2 seasons and 12 episodes so far and has ended. The latest episode, Season 2 Episode 6, aired on August 5, 2026.

In the post-pandemic world of 2024 during an upcoming British general election involving the UK’s first Black Conservative prime minister, a leading team of analysts at the heart of the UK’s NSA-style spy agency GCHQ attempt to ward off a cyber-attack on the country’s electoral system.

  • Sci-Fi & Fantasy
  • Drama
  • War & Politics

Last updated

Episodes

12 episodes · 2 seasons

Series 1

2022 · 6 episodes · Last episode: 4 years ago

The Undeclared War Series 1 release dates →
  1. The Undeclared War S1 E6 still E6

    6. Episode 6

    Finale

    As the true extent of Russia's interference with the UK becomes clear, Saara and her former classmate join forces. Can they uncover the hidden code and prevent a war?

  2. The Undeclared War S1 E5 still E5

    5. Episode 5

    Signs of irregularity in the UK general election result prompt political unrest, and the nation's relationship with its allies is threatened. Saara makes a devastating discovery.

  3. The Undeclared War S1 E4 still E4

    4. Episode 4

    With Saara in a difficult position, a revelation forces her hand. Marina moves to London.

  4. The Undeclared War S1 E3 still E3

    3. Episode 3

    Vadim returns to Russia where his allegiances are tested, leading him to a risky stunt.

  5. The Undeclared War S1 E2 still E2

    2. Episode 2

    Saara befriends John, a veteran GCHQ staffer, and seeks help from Gabriel in decrypting a message in the virus. Danny signs off on Saara attending a cyber conference with US agent Kathy, aware that Russian intelligence will also be there.

  6. The Undeclared War S1 E1 still E1

    1. Episode 1

    A young intern's first day at GCHQ coincides with a major cyberattack on the UK. To win her superiors' trust, she breaks ranks to analyse the malware code without permission and uncovers a greater threat missed by others.

Series 2

2026 · 6 episodes · Last episode: 3 months ago

The elite Malware Department at GCHQ grapples with the aftermath of a devastating Russian cyber-attack. Just when it seems the UK has gained the upper hand, Danny and his team discover a mole in their midst and uncover a far more dangerous threat.

The Undeclared War Series 2 release dates →
  1. The Undeclared War S2 E6 still E6

    6. Episode 6

    Finale

    Danny puts everything on the line in order to right some wrongs.

  2. The Undeclared War S2 E5 still E5

    5. Episode 5

    Charlie interrogates Barbara, and Danny discovers a clue that turns his life upside down.

  3. The Undeclared War S2 E4 still E4

    4. Episode 4

    A malware attack on British government departments forces Danny and Roz to work together.

  4. The Undeclared War S2 E3 still E3

    3. Episode 3

    Barbara faces an impossible decision when her charming ex-boyfriend Nicky Chan re-appears.

  5. The Undeclared War S2 E2 still E2

    2. Episode 2

    Vadim finds himself working for the Chinese. Danny and Roz clash, and the mole hunt is on.

  6. The Undeclared War S2 E1 still E1

    1. Episode 1

    As Danny deals with the fallout from the Russian cyber-attack, a bold new threat emerges.

Cast & crew

Created by Peter Kosminsky

  • Mark Rylance

    Mark Rylance

    John Yeabsley

  • Julie Barclay

    Julie Barclay

    Sally J

  • Kirsty Hoiles

    Kirsty Hoiles

    Caroline Fitch

  • Nitin Ganatra

    Nitin Ganatra

    Ahmed Parvin

  • Gavi Singh Chera

    Gavi Singh Chera

    Sajid Parvin

  • Robert Cavanah

    Campbell Scott

  • Alfie Friedman

    Gabriel Davies

  • Melanie Gutteridge

    Melanie Gutteridge

    Chrissie

  • Aysha Kala

    Aysha Kala

    Amina Parvin

  • Jamie Muscato

    Jamie Muscato

    Finn

  • Andrew Rothney

    Andrew Rothney

    Rich T

  • Rick Bithell

    ITN Reporter

  • Nik Howden

    Adjudicator

  • Zaqi Ismail

    Zaqi Ismail

    Zahir

  • Tom McKay

    Tom McKay

    Max K

  • Joss Porter

    Joss Porter

    Phil D

The Undeclared War FAQ

Will there be new episodes of The Undeclared War?

The Undeclared War has ended, so no new episodes are scheduled. The final episode aired on August 5, 2026.

When did the latest episode of The Undeclared War come out?

The most recent episode of The Undeclared War, Season 2 Episode 6, aired on August 5, 2026.

How many seasons of The Undeclared War are there?

The Undeclared War has 2 seasons with 12 episodes in total.

When did The Undeclared War first air?

The Undeclared War first aired on Channel 4 on June 30, 2022.

How do I get notified when new episodes of The Undeclared War are released?

Download the Streambay app, follow The Undeclared War, and you'll get a push notification the moment each new episode is released.

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