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Tear Jerker: V For Vendetta
Mitigated somewhat when Evie finds out that it was part of a Mind Screw by V. Back in full force when V tells her that he didn't write the letter, but received it exactly as she did.
Also, the fate of the young girl in the movie version during the VO by Detective Finch describing how "someone will do something stupid", showing that one of the Fingermen had shot her for spray-painting V over a propaganda sign.
Of course, that's followed by instant karma. And may well be the trigger of the revolution.
In the movie, V kneeling down and weeping after Evey's departure serves to humanize him beyond the faceless anarchist, and the small crack in his suave mask is hard to watch. Tearstorm ensues.
In the book, there's the part during Finch's LSD trip where he sees the smiling, laughing faces of all the people killed at Larkhill, and is filled with remorse for what the regime has done... and then they all run away and disappear...