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The Best Episodes of The Undeclared War

Every episode of The Undeclared War ranked from best to worst. Let's dive into the Best Episodes of The Undeclared War!

Best episode
S2E6 Episode 6
7.9126 votes
Worst episode
S2E3 Episode 3
7.0137 votes
Top season
Season 2
7.3avg
Binge time
9h 32m
12 episodes

Seasons2

Episode Rankings

  1. #1 Fan Favorite
    Click to reveal
    The Undeclared War Season 2 Episode 6 - Episode 6
    7.9/10(126 votes)
    S2:E6

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

    Director:Unknown
    Writer:Unknown

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  2. The Undeclared War Season 2 Episode 5 - Episode 5
    7.5/10(117 votes)
    S2:E5

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

    Director:Unknown
    Writer:Unknown

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  3. The Undeclared War Season 2 Episode 4 - Episode 4
    7.4/10(130 votes)
    S2:E4

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

    Director:Unknown
    Writer:Unknown

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  4. The Undeclared War Season 1 Episode 6 - Episode 6
    7.3/10(375 votes)
    S1:E6

    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?

    Director:Unknown
    Writer:Unknown

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  5. The Undeclared War Season 1 Episode 3 - Episode 3
    7.2/10(369 votes)
    S1:E3

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

    Director:Unknown
    Writer:Unknown

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  6. The Undeclared War Season 2 Episode 1 - Episode 1
    7.1/10(162 votes)
    S2:E1

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

    Director:Unknown
    Writer:Unknown

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    The 20 WORST Episodes of The Undeclared War

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  8. The Undeclared War Season 1 Episode 5 - Episode 5
    7.1/10(317 votes)
    S1:E5

    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.

    Director:Unknown
    Writer:Unknown

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  9. The Undeclared War Season 1 Episode 4 - Episode 4
    7.1/10(322 votes)
    S1:E4

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

    Director:Unknown
    Writer:Unknown

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  10. The Undeclared War Season 1 Episode 2 - Episode 2
    7.1/10(390 votes)
    S1:E2

    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.

    Director:Unknown
    Writer:Unknown

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  11. The Undeclared War Season 1 Episode 1 - Episode 1
    7.1/10(500 votes)
    S1:E1

    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.

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  12. The Undeclared War Season 2 Episode 2 - Episode 2
    7.0/10(133 votes)
    S2:E2

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

    Director:Unknown
    Writer:Unknown

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  13. The Undeclared War Season 2 Episode 3 - Episode 3
    7.0/10(137 votes)
    S2:E3

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

    Director:Unknown
    Writer:Unknown

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Best Episodes Summary

"Episode 6" is the best rated episode of The Undeclared War. It scored 7.9/10 from 126 votes. Written and directed by Unknown, it aired on August 5, 2026. This episode scored 0.4 points higher than the second highest rated, "Episode 5".

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