Question: What kept the police from going into the sewers to retrieve Oswald?
Question: Why exactly does Penguin die? He just falls into his "moat" and comes out bleeding and dying. He wasn't hurt by the bats too much. He made reference to there being a "toxic" lagoon earlier in the movie, so are we to assume the water is polluted by toxic chemicals? And if so, how can the penguins swim in it without being hurt?
Question: It is never explained why Catwoman hates Batman enough to attack him during their first encounter. A day or two earlier, when she was just Selina Kyle, Batman had actually saved her from one of the thugs rioting in Gotham City, so there is no reason for her to be so aggressive towards him (other than the fact that the audience expects them to be enemies, which is no explanation at all). Why does she?
Question: The penguins were left behind when the zoo closed. Who/what kept them alive? Oswald?