: Are you thinking of the series finale, "Enemy at the Gate" ? Technically, this is Season 5, Episode 20 , but it’s the definitive "Enemy" episode for the franchise, featuring the final showdown between the Wraith and Earth. (Season 4, Episode 5 of Atlantis is actually titled " Travelers " ).
: Are you interested in the penultimate episode of the most recent season, Season 4, Episode 5 , titled " Grave Danger " ? It features Frank Harkness making a major move against Slough House. [S4E5] Enemy at the Gates
It looks like there’s a bit of a mix-up with episode titles and numbers across different shows! The phrase "Enemy at the Gate" is a very famous title, but it matches a few different iconic series in slightly different ways. : Are you thinking of the series finale, "Enemy at the Gate"
:This episode is actually titled "Beware the Jabberwock, My Son," but it deals with a high-stakes "enemy within" plot involving a supe-killing virus and the return of Stan Edgar. : Are you interested in the penultimate episode
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