Cuarón told i09 that Warner Bros. said, “’you need to cut to Houston, and see how the rescue mission goes. And there is a ticking clock with the rescue mission. You have to do flashbacks with the backstory.’ But we were very clear that this was the film that we wanted to make.”
He continues, saying, “[They wanted] the whole thing of the flashbacks. A whole thing with… a romantic relationship with the Mission Control Commander, who is in love with her. All of that kind of stuff. What else? To finish with a whole rescue helicopter, that would come and rescue her. Stuff like that.”
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Warner Bros. reportedly asked him things like, “Are you sure you don’t need to pump up the action value, like having an enemy, like a missile strike?”