Image credit: HBO
Warning: Spoilers ahead for Game of Thrones Season 6.
Sunday's episode of Game of Thrones, titled "The Door", had one of the most heart-breaking deaths in the series so far. Not only did Hodor die to protect Bran and Meera, but we finally learn why he only ever said the word "Hodor".
When Hodor was a young boy, named Wylis, Bran Stark accidentally time traveled and warged Wylis into his future Hodor self, so that he witnessed his own death.
It turns out that this was part of George R.R. Martin's plan along. In the "Inside the Episode" featurette for Season 6, Episode 5, showrunners David Benioff and D.B. Weiss explained how Martin told them about Hodor's origins.
"We had this meeting with George Martin where we're trying to get as much information as possible out of him," Benioff said. "Probably the most shocking revelation he had for us was when he told us the origin of Hodor, and how that name came about. I just remember [Weiss] and I looking at each other when he said and being like 'holy s---.'"
With the show's story going beyond Martin's book series, it's often tough for book readers to know if the events in the show will play out the way in the books. So when the showrunners confirm that certain parts of the storyline came from Martin himself, there's added weight to those scenes for some readers.
"It was just one of the saddest and most affecting things," Weiss explained. "Even sitting in a hotel room and having somebody tell you this was going to happen in the abstract ... and that 'hold the door' was the origin of the name Hodor. We just thought that was a really really heartbreaking idea."
You can watch the featurette below. They start speaking about Hodor at 3:55.
Game of Thrones airs on Sunday nights at 9 p.m. E.T.