: 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.
: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. [S4E5] Enemy at the Gates
Could you clarify which show you are looking for a deep dive on? Here are the most likely candidates: : Are you interested in the penultimate episode