* ActorAllusion: It seems that John Hurt [[Literature/NineteenEightyFour always had a lot of experience]] [[Film/VForVendetta with British political extremes and secret services]].
* DawsonCasting: Karla's daughter is supposed to be in her twenties but the actress is in her thirties.
* DyeingForYourArt:
** Oldman's hair (lighter) and waistline (heavier).
** Cumberbatch as well - Guillam's hair is blonde, while Mr. Cumberbatch is naturally a ginger.
* PlayingAgainstType: Creator/ColinFirth and Creator/MarkStrong co-star in a movie where one plays a kindly schoolteacher haunted by his past, and one plays a depraved turncoat spy selling international secrets to the Soviets. [[spoiler: Sounds pretty typical, unless you know that Strong's the schoolteacher and Firth's the evil spy]].
* WhatCouldHaveBeen: ''Film/{{Oldboy|2003}}'' director Creator/ParkChanWook was offered the film at one point.
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