"They originally came to me around an episode that referenced New York, this was a while back," says Mayor de Blasio of his cameo on Sunday's episode. "Then they came back and said they had this episode where Grandpa comes to New York City and they wanted to do an encounter with me. I was like: Anything Simpsons, I’m into. When you get invited into something that you truly love and truly admire, it’s like an otherworldly feeling — like crossing over into a new realm. The line between fact and fiction gets a little blurred. Are we real and the show is fake, or the other way around?"