One of the lessons that Chris and I learned from Batman was that if you're going to revitalize an iconic figure like that, you have to be prepared to slay some sacred cows and you have to be prepared to weather the slings and arrows of some people. You have to respect the canon, but constantly question the canon. If you don't reinvent these characters -- and they are constantly being reinvented in the comic books -- then they become stagnant and they cease being relevant. We were feeling -- and I think a lot of people were feeling -- that Superman was ceasing to be relevant.
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Killing Zod was a big thing and that was something that Chris Nolan originally said there's no way you can do this. That was a change. Originally, Zod got sucked into the Phantom Zone along with the others. I just felt it was unsatisfying and so did Zack. We started questioning and talked to some of the people at DC Comics and said, "Do you think there's ever a way that Superman would kill someone." At first they said, "No way. No way." We said, "But what if he didn't have a choice?" Originally, Chris didn't even want to let us try to write it. Zack and I said, "We think we can figure out a way that you'll buy it." I came up with this idea of the heat vision and these people about to die. I wrote the scene and I gave it to Chris and he said, "OK, you convinced me. I buy it."
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I think it makes some people feel uncomfortable; other people say, "Right on." That was the point. Hopefully what we've done with the end of the film is we've gotten people -- the mainstream audience, not the geek audience -- to question [the character]. Hopefully we've redefined Superman.