1) The Dark Knight Returns
When Batman V Superman was first announced, fans were excited that the movie might be a close adaptation of the acclaimed The Dark Knight Returns, a graphic novel by Frank Miller which sees an older, embittered Batman fighting with Superman. The film is actually very different from that comic, but there were still many nods to it hidden throughout.
These include visuals lifted from Returns, like Batman’s enhanced metal suit in his fight with Supes and the unusual sight of him carrying guns, something he also does in that story. Events such as Superman regenerating himself after being hit by a nuclear bomb and most notably the death of the Waynes – with Martha’s pearls hooking onto her killer’s gun – are also borrowed from the graphic novel.
A few lines of dialogue are repeated wholesale here as well, such as Alfred’s “I hope the next generation of Waynes don’t inherit an empty wine cellar” and Batman’s “I believe you” to Knyazev when he says he’ll kill Martha.