"I couldn’t believe it," David Benioff says in James Hibberd's upcoming Game of Thrones book Fire Cannot Kill a Dragon, according to The Hollywood Reporter. "When we got the email about it the next day, I honestly thought someone was pranking us, because there had been things before where people were like, 'Oh, look at that plane in the background!' and somebody had Photoshopped it in. I thought, 'There’s no way there’s a coffee cup in there.' Then when I saw it on the TV I was like, 'How did I not see that?'” Fellow co-creator D.B. Weiss adds: "I’d seen that shot one thousand times and we’re always looking at their faces or how the shot sat with the shots on either side of it. I felt like we were the participants in a psychology experiment, like where you don’t see the gorillas running around in the background because you’re counting the basketballs."