Trivia: During the big fight between Batman and Superman, a broken window has the same shape as Ontario, in Canada. Superman creator Joel Shuster was born in Toronto. The broken window is only ever shown from Superman's angle, not Batman's. This was confirmed by Zack Snyder as being a deliberate, if obscure, easter egg.
Trivia: When the crime lab calls for Lois, we see a nameplate on the cubicle wall saying "Liz Ritenour. Photo Editor." Ritenour is an assistant in the art department for the film, as well as the upcoming Justice League film.
Trivia: Lex Luthor's prison garb has the prisoner number of 16-TK421. TK421 is a reference to Star Wars when Luke and Han take on Stormtrooper disguises.
Trivia: Zack Snyder didn't want to call the film "Batman v Superman." He and writer Chris Terrio pitched multiple other titles first. Snyder wanted something more flowery, like "Son of Sun and Knight of Night, " which the studio absolutely hated, while Terrio suggested titles like "Justice League: Foundations," since it was showing how the first members of the Justice League came together. The studio wanted something more straightforward and marketable, and "Batman v Superman" was eventually picked.
Trivia: During Batman and Superman's fight scene, there is a shot of some graffiti that says "Quis custodiet ipsos custodes?", which is Latin for, "Who watches the watchers?" This is a reference to "Watchmen", which was also directed by Zack Snyder, and also references the theme of both films.
Trivia: In a deleted scene near the end of the film after Luthor is arrested, a guard calls Luthor prisoner AC231940 and tells him to turn around. Action Comics #23 was Lexus Luthor's first appearance in 1940.
Trivia: Dr. Silas Stone refers to the Mother Box recovered by S.T.A.R. Labs as government object #6-1982. Cyborg's first ever solo comic, Tales of the New Teen Titans #1 (which detailed his origins), was released in June, 1982.
Trivia: On Bruce Wayne's bulletin board, there is a photo of Superman holding up a car, very similar to the cover of Superman #1 in 1938. There is a similar picture of Superman on Wally's wall.
Trivia: Perry White tells Clark Kent "it's not 1938," which is the year of Action Comics #1, the first appearance of Superman.
Chosen answer: The beginning is Bruce Wayne's perspective of the events that occurred in the movie "Man of Steel" when Superman and General Zod are fighting (if you haven't seen it, it would explain a lot of BvS events). It's General Zod's ship and the phantom drive. It cuts to 18 months later. Supermen is called to testify in front of a congressional hearing because of his vigilantism over the past 18 months and people are concerned about his actions (like the events in Africa) since he's an all-powerful alien with no way for the people to stop him, so they're very nervous. Bruce seems to blame Superman more than anyone though for the destruction and death of people he knew (and tried to save) because if Superman wasn't on Earth, Zod wouldn't have come to Earth, etc.
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